Tag Archives: SFT40

Wurkkos TD01

The TD01 is a budget tactical flashlight featuring a TIR lens for maximum throw with minimal spill. Powered by a single included 21700 battery, with both tactical and general user interface options.

  1. Introduction
  2. Manufacturer Specifications
  3. Package Details
  4. Build
  5. User Interface
  6. Circuit Measures
  7. Emitter Measures
  8. Beamshots
  9. Testing Results
  10. Runtimes
  11. Pros and Cons
  12. Overall Rating
  13. Preliminary Conclusions
  14. Acknowledgement

Introduction

The TD01 is a new tactical/hunting-style flashlight from Wurrkos. Featuring the low-profile Luminus SFT40 coupled with a large focused TIR, this 1×21700 flashlight is clearly designed to be a dedicated thrower. I was certainly impressed with the compact TS22 from Wurkkos, so am happy review this larger thower model.

Physically, the light is still fairly compact for having such a large head. There is also a tailcap forward clicky switch, coupled with an electronic side switch in the head. This design is very reminiscent of the reflectored Sofirn C8L – a comparison which, as we will see, runs more than skin deep.

Let’s see how it compares in my testing.

Manufacturer Specifications

Note: as always, these are simply what the manufacturer provides – scroll down to see my actual runtimes.

FeatureSpecs
MakerWurkkos
ModelTD01
EmitterSFT40
Tint6000 - 6500 K
Max Output (Lumens)2,200
Min Output (Lumens)30
Max Runtime70 hours
Max Beam Intensity (cd)270,000 cd
Max Beam Distance (m)1039 m
Constant Levels5
FlashingStrobe, SOS, Beacon
Battery1x21700
Weight (w/o battery)
Weight (with battery)200 g
Length152 mm
Head Diameter59 mm
Body Diameter-
WaterproofIPX-8

Package Details





I really like the packaging of the higher-end lights from Wurkkos (and Sofirn, which share a common manufacturing plant). The hard-sided box comes with a lot of printed specs on the sleeve, and a clear separation of items and components inside thanks to the cut-out foam. Inside the box, I found:

  • Wurkkos TD01 flashlight
  • Wurkkos-branded 5000mAh 21700 battery
  • Wrist lanyard
  • USB-C charging cable
  • 2 Spare O-rings
  • Manual

It’s a decent package for a “budget” build, but I would really like to see a holster included. These form factor lights tend not to fit well into after-market holsters.

Build


From left to right: LiitoKala 21700 (5000mAh), Acebeam 21700 USB-C (5100mAh), Lumintop D3, Convoy M21F, Sofirn C8L, Wurkkos TS30S Pro, Wurkkos TD01, Acebeam L19 V2.0, Acebeam P17.










The Wurkkos TD01 immediately reminds me a lot of the Sofirn C8L in its overall build and feel. This is not surprising, since these lights come off the same manufacturing production line. I will get into the specifics below, but it is a solid build overall, with good handfeel. I would rate it as above average quality for a budget light, but lacking some of the nicer touches of a true top-of-the-line light. And while substantial in overall dimensions and weight, it is still pocket-able to some degree (i.e., with the head protruding out).

Like the C8L, there is a physical forward clicky switch in the tailcap, used for the turning the light on/off. However, switch feel is not as good on this particular sample – I find it too “soft and squishy” (i.e., you need to press more than expected to activate in momentary mode, and it’s too easy to then accidentally click). This makes momentary or a double-press (required to jump to Turbo from Off) tricky to do consistently. See the user interface section below for more information.

There are two raised tailcap guards that can serve as the lanyard attachment point. However, unlike the C8L (which had exact same arrangement), my TD01 is not able to tailstand at all – the tactical switch protrudes too far, beyond the switch guard rails. This is a missed opportunity on this model (or at least, this sample).

Tailcap threads are square-cut and anodized, with good feel. I always recommend you keep a light stored locked out when not in use. Thanks to the anodized tailcap threads, you can do this easily on the TD01 by a simple twist of the tailcap.

There is a raised side-mounted electronic switch on the side of the head, with red and green LEDs underneath to show charge status. Feel and traverse of the electronic switch is very similar to a lot of Wurkkos and Sofirn lights – it’s ok, but could be a bit tighter/firmer (i.e., hard switch covers always have some degree of play).

The side switch shines a bright red when charging the battery through the light’s USB-C charging port (green when fully charged). The port is located on the opposite side from the switch, under a rubber cover. The cover fits pretty well on the TD01 (just like the C8L) – not too too tight, not too loose. I expected waterproofness is reasonable.

There is no actual knurling on the light, but large raised concentric rings around the body tube help with grip (pattern is virtually identical to the Wurkkos TS22). When combined with the head and tailcap ridge detail, I would say overall grip is pretty good. Note that the light can roll away completely unfettered when on its side – the head has a completely smooth round edge, and lacks any cut-outs of any kind (even the C8L had some gentle ones, to help reduce roll a little). I recommend you stand it upright on its head when not in use. Anodizing looks to be good quality for type II, with no damage on my sample. I would describe the finish as satin.

Inside, the light comes with a Wurkkos-branded standard-sized 5000mAh 21700 battery, with a slightly raised flat-top. There is a good size spring in the head, ensuring good contact (always a good idea for a “tactical” light).

As with all things, it comes down to your expectations. The TD01’s build is a very good approximation of a quality tactical light, but it does have a number of small issues and inconsistencies that add up (and reflect its budget status).






The TD01 uses a very distinctive large TIR optic looks a lot like the Acebeam L19, except with a thicker centre “column.” I’ve taken pics from a lot of angles above, so you can see how it generally obscures the emitter (except in the second shot above). The low-profile SFT40 is ideal for producing a very focused beam, which the TD01 does very well.

The bezel is crenelated black aluminum – not too aggressive, so you can headstand stably. Note that some of the promotional material seems to suggest the light has a stainless steel strike bezel – it doesn’t, just this low profile aluminum bezel (again, in keeping with its budget nature). There doesn’t seem to be any kind of anti-reflective coating on the lens.

Here are a couple of white wall beamshots, to give you an idea of how focused it is:


I’ve included the white wall beamshots above to highlight a single bright ring that is visible in the mid-distance around the hotspot. Note that in real life the hotpot is much smaller than it appears above (the camera settings are over-saturating the hotspot intensity). But I’ve chosen these settings to better show you the ring. Rest assured, the ring is not that distracting in real life, but it is present (scroll down for outdoor beamshots).

User Interface

The TD01 has a user interface that is identical to the Sofirn C8L, again reflecting their shared heritage. Like many “tactical” lights, you have two sets of possible modes; Mode Group 1 for General use, and Mode Group 2 for Tactical use.

To switch between groups, press-and-hold the side switch for >3 secs when On.

Mode Group 1 (default) available levels: Eco, Low, Medium, High, Turbo, Strobe, SOS, and Beacon.

Mode Group 1, from OFF:

  • Tail switch, partial-press: Momentary On in last memorized mode.
  • Tail switch, single-click: Turns On in last memorized mode.
  • Tail switch, double-press: Turns On in last memorized mode and then jumps to Turbo (click to stay locked-on in Turbo). You have be very rapid on the double-press to jump to Turbo.
  • Side switch, press-and-hold: Nothing – but if you click the tail switch while holding down the side switch, the light will activate in Eco mode.
  • Side switch, single-click: Nothing.

Mode Group 1, from ON:

  • Tail switch, partial-press: Nothing.
  • Tail switch, single-click: Turns Off.
  • Side switch, press-and-hold (3 secs): Switch to Mode Group 2 (see below)
  • Side switch, single-click: Steps up to the next non-Turbo constant output mode (in sequence, Eco > Lo > Med > High).
  • Side switch, double-click: Turbo.
  • Side switch, triple-click: Strobe.
    • Side switch, double-click when in Strobe: Cycle through in sequence Strobe > SOS > Beacon (with no mode memory).

Mode 1, Mode memory:

Yes, for non-Turbo constant output modes.

Mode 1 Shortcuts:

  • Eco mode: Press and hold the side switch while turning on at the tail switch.
  • Turbo mode: Double-click the side switch from On, or double-press the tail switch from Off.

Mode 2 available levels: Medium, Turbo, and Strobe.

Mode 2 functions basically as a stripped-down “tactical” version of Mode 1. The main differences are:

  • Single-click of the side switch from On only selects between Medium and Turbo now.
  • Double-click of the the tail or side switch goes to Strobe instead of Turbo.
  • There is no level memory now.

Otherwise, the two modes function the same way.

Battery indicator:

When first activating the light, the indicator on the side switch shows the battery voltage  (lasts for ~5 secs):

  • Solid green: ~70-100%
  • Flashing green: ~40-70%
  • Solid red: ~10-40%
  • Flashing red: 0-10%

Mode memory:

Yes, in the Mode Group 1 for non-Turbo constant output modes. There is no memory in the Mode Group 2.

Shortcuts:

  • Mode Group 1: Yes, for Eco, Turbo and Strobe (see above).
  • Mode Group 2: Yes, for Eco and Strobe (see above).

Low voltage warning:

Yes, the main light will step down as the battery is running low. It will then turn Off at ~2.95V

Lock-out mode:

Yes, but physically – you lock-out the light by a twist of the tailcap.

Reviewer Comments:

As with the build, I think this is a reasonable dual-mode UI for a tactical light, with a general mode set and a tactical mode set.

One thing I’m not crazy about is the multiple-press functionality of the tactical tailcap switch. I didn’t really find this as much of an issue on the C8L, but my TD01’s switch is noticeably softer. This made it harder to consistently double-click the tailcap (i.e., soft-press, then press-and-click rapidly). But in any case, this level switching feature at the tailcap is completely unnecessary on the C8L/TD01 anyway, as you always have the electronic side switch in the head to control output levels (including accessing Turbo).

On the whole, I personally prefer General Mode Group 1, for its versatility. I suppose “tactical” people will like the lack of mode memory in Tactical Mode Group 2.

Circuit Measures

Pulse-Width Modulation (PWM):

Eco:
Eco

Low:
Lo

Mid:
Mid

High:
Hi

Turbo:
Turbo

There is high frequency circuit noise on all levels except Turbo on the TD01, at a visually undetectable constant frequency of 19.9 kHz. This is different from the C8L, which was completely noise free. As is often the case, this constant circuit noise increases in amplitude with output level. It is definitely not PWM, although it has a bimodal distribution (i.e., there is a secondary harmonic of rising/cresting waves at ~5 kHz), as shown in the expanded view of the High mode below

Turbo

Again, this is not a problem per se, as you won’t be able to see any of the above in use. But from long experience, I find this doesn’t bode well when it comes to overall circuit regulation and efficiency (scroll down for runtimes).

Strobes:

Strobe:


Strobe alternates between 8 Hz and 14 Hz every 2 secs or so. Very distracting.

SOS:

A standard SOS mode, relatively slow.

Beacon:

A single flash beacon once every 2 secs (0.5 Hz).

Charging:

The switch button shows solid red when the light is charging. Changes to solid green when the charging is complete.

Resting voltage <3.0V

Resting voltage >3.0V

The TD01 has a two-stage charging feature, as seen on many modern lights (although oddly, not its sister light the C8L) where there is a lower initial charging rate when the cell is heavily discharged. The initial charging rate is ~0.25A, which jumps to ~1.55A once the cell exceeds 3.0V resting. These rates are good for a 21700 cell. Charging terminated at ~4.19V on my sample. This is probably the first example where the TD01 has a slight advantage over the C8L.

Standby / Parasitic Drain:

None. That is one of the nice things about a physical clicky switch, no standby current. 🙂 And you can always lock-out the light by a twist of the tailcap, to prevent accidental activation.

Emitter Measures

In this section, I directly measure key emitter characteristics in terms of colour temperature, tint, and colour rendition. Please see my Emitter Measures page to learn more about what these terms mean, and how I am measuring them. As tint in particular can shift across levels, I typically stick with the highest stably regulated level for all my reported measures.

As explained on that page, since I am using an inexpensive uncalibrated device, you can only make relative comparisons across my reviews (i.e., don’t take these numbers as absolutely accurate values, but as relatively consistent across lights in my testing).

TD01 on Med:

The key measures above are the colour temperature of ~6045K, and a noticeably positive tint shift (+0.0138 Duv) to greenish-yellow at this temperature. For CRI (Ra), I measured a combined score of 64.

These values are very consistent with the rated specs for the cool white SFT40 emitter on my sample, and match my visual experience of this light.

Beamshots

All long-distance outdoor beamshots are taken on my Canon PowerShot S5 IS at f/2.7, 1 sec exposure, ISO 400, daylight white balance. The tree at the centre of the hotspot is approximately 90 meters (~100 yards) from the camera. Note the road dips down and turns away in the distance, out of the camera’s sight line. Learn more about my outdoor beamshot locations here.

Click on any thumbnail image below to open a full size image in a new window. You can then easily compare the overall beams by switching between tabs.



To help illustrate the hotspots better, I’ve also cropped the raw pictures around the centre of the frame. As before, click on any thumbnail below to open a full size image in a new window.



As you can see above, the TD01 is a very focused thrower. It does put out a little more light into the periphery than the L19, and with a slightly larger hotspot. But this is an incredible thrower.

Testing Results

My summary tables are generally reported in a manner consistent with the ANSI FL-1 standard for flashlight testing. In addition to the links above, please see my output measures page for more background.

All my output numbers are based on my home-made lightbox setup. As explained on that methodology page, I have devised a method for converting my lightbox relative output values to estimated lumens. Note that my lightbox calibration seems to run higher than most hobbyists today, but I’ve kept it to remain consistent with my earlier reviews (when the calibration standard was first established).

My Peak Intensity/Beam Distance are directly measured with a NIST-certified Extech EA31 lightmeter.

TD01 Testing Results

ModeSpec LumensEstimated Lumens @0secEstimated Lumens @30 secsBeam Intensity @0secBeam Intensity @30secsBeam Distance @30secsPWM/Strobe FreqNoise FreqCharging Current <3VCharging Current >3VParasitic DrainWeight w/o BatteryWeight with BatteryCCT (K)DuvCRI
Eco302928---No19.858 Hz0.25 A1.55 ANo193 g261 g---
Low150155150---No19.858 Hz0.25 A1.55 ANo193 g261 g---
Med350290285---No19.864 Hz0.25 A1.55 ANo193 g261 g6,0450.013864
High900760740---No19.878 Hz0.25 A1.55 ANo193 g261 g---
Turbo2,2002,1002,000255,000 cd235,000 cd970 mNo-0.25 A1.55 ANo193 g261 g---
Strobe2,200-----8-14 Hz-0.25 A1.55 ANo193 g261 g---
SOS350------19.858 Hz0.25 A1.55 ANo193 g261 g---
Beacon2,200-----0.5 Hz-0.25 A1.55 ANo193 g261 g---

Unlike my TS22 and C8L samples, the TD01 has inflated specs on its higher levels, compared to what I measure in my lightbox. Oddly, it’s worse on the Med and Hi levels, with Turbo only being inflated by ~10% in my lightbox. Although it is probably even worse than the numbers above suggest, as I know my lightbox’s relative calibration is generously high for modern high-output lights.

My NIST-calibrated luxmeter is accurately calibrated to an absolute standard, and reports slightly lower beam intensity on Turbo (comparable to my lightbox for overall output measures). But this is still an impressive showing.

To view and download full testing results for all modern lights in my testing, check out my Database page.

Runtimes

As always, my runtimes are done under a small cooling fan, for safety and consistency. To learn more about how to interpret runtime graphs, see my runtimes methodology page.

Max

Hi

Med

One thing these results make very clear: Wurkkos is definitely not using a buck driver on the TD01. There had been some apparent miscommunication on this point when the light was first announced. It appears to be using a standard FET driver, producing the non-voltage-regulated runtimes you see above.

In and of itself, this is not necessarily a problem – such lights can still be relatively efficient. But that doesn’t really seem to be the case here. It is not as efficient as the Convoy S21E that I tested with this same SFT40 emitter – that light had perfectly flat regulated output (which lowers overall efficiency, since it spends a lot more time at higher output, plus has circuit overhead to consider). So performance here is disappointing, especially in comparison to the outstanding efficiency and regulation that you can see on the TS22 and the Sofirn C8L.

You can also see that the TD01 steps down very quickly on Turbo and Hi. To better show this initial step-down pattern, here is a expanded view of first few minutes of those runtimes:

Max-extended

Pros and Cons

ProsCons
As advertised, the light is a very dedicated thrower, thanks to its large focused TIR optic.Circuit is not voltage-regulated, producing a slowly decreasing output instead of flat runtimes. It also appears to be less efficient then other current-controlled lights with flat regulation.
The light has a solid build with good handfeel, although there are some small issues (see Cons).Tactical forward clicky switch has a softer feel than typical, making signalling or double-clicking difficult. It also protrudes too far, preventing tailstanding.
Price is incredibly low, making this arguably the best throwing light of the 1x21700 class at this price point.Light can roll very easily, with no preventive measures to impeed.
Output specs seem to be somewhat inflated.
Would really benefit from an included holster.

Overall Rating

Preliminary Conclusions

Many of my build observations of the Sofirn C8L are true here as well – in many ways, this is a sister light to that model, but one that is heavily focused for throw. The lights are very similar in overall build quality and packaging, reflecting the common factory they are produced at (despite being different companies). The dual physical tailcap clicky and side electronic switch design – along with an identical user interface – further cements their close relationship.

But the switches are where I find the comparison starts to break, and not in the TD01’s favour. The switch feel is softer on my TD01 sample than the C8L, limiting its value for momentary signalling. And because it protrudes further than my C8L sample, the TD01 doesn’t tailstand at all, which is disappointing. Not a huge deal of course, but it is a minor annoyance that could easily have been avoided.

Overall output/runtime efficiency is fine for a SFT40 emitter, but overall output is lower than rated for the specs on this model. And unfortunately regulation is disappointing here too – especially against the outstanding TS22 and Sofirn C8L. It looks like Wurkkos simply reused an older driver/circuit for the SFT40 emitter, and updated it with the C8L’s user interface. I would have preferred to see a fully voltage-regulated pattern here.

Beam pattern is very throwy as advertised, and I find the TIR optic does a really good job of focusing almost exclusively for throw. There is just one noticeable beam ring – but that’s more an issue on a white wall than in actual use outdoors. It really is quite the spotlight!

Despite the close similarities to the C8L – and the impressive TIR optic here – I can’t give this light higher than 3.5 stars in its current form. The physical quirks with the switch, and the more significant circuit issues (i.e., off from the specs, lower sustained output, lack of voltage regulation, reduced efficiency, circuit noise, etc.) knock this light down a full star from the C8L in my view.

It is still an incredible value for the price, and I appreciate all that it does bring to the table. If the issues above don’t matter to you, this is a great way to experience massive TIR throw at a budget price (it really is unbelievably cheap!). As the beamshots show, that is an incredible beam. With a little more fine-tuning, this could become a top pick in the dedicated TIR thrower class.

Acknowledgement

The TD01 was supplied by Wurkkos for review. As always, all opinions are my own and the light received the same rigourous and objective testing as all other lights that I have reviewed. At the time of review, this light retails for ~$45 USD (~$60 CDN) with typical discounts on their website here.

Nitecore MH12SE

The MH12SE is the sixth iteration of the general-purpose MH12 line of flashlights. Features an integrated battery charging feature and single included 21700 battery.

  1. Introduction
  2. Manufacturer Specifications
  3. Package Details
  4. Build
  5. User Interface
  6. Circuit Measures
  7. Emitter Measures
  8. Beamshots
  9. Testing Results
  10. Runtimes
  11. Pros and Cons
  12. Overall Rating
  13. Preliminary Conclusions
  14. Acknowledgement

Introduction

Following on my P20iX review, this is the latest iteration of the MH12 series from Nitecore – now up to the MH12SE, which is apparently its sixth iteration. Featuring a 1×21700 battery and dual physical tail clicky/electronic side switches, the “multi-task hybrid” series has clearly come a long way.

This light features the Luminus SFT-40-W emitter, which is a low-profile “flat window” emitter (i.e., no dome). This translates into better throw, typically at the expense of some output. Let’s see how it does in my testing.

Manufacturer Specifications

Note: as always, these are simply what the manufacturer provides – scroll down to see my actual testing results.

FeatureSpecs
MakerNitecore
ModelMH12SE
EmitterSFT40-W
Tint-
Max Output (Lumens)1,800
Min Output (Lumens)1
Max Runtime1,500 hrs
Max Beam Intensity (cd)41,000 cd
Max Beam Distance (m)405 m
Mode Levels5
FlashingStrobe, Beacon, SOS
Battery1x21700
Weight (w/o battery)80 g
Weight (with battery)-
Length141 mm
Head Diameter25.4 mm
Body Diameter25.4 mm
WaterproofIP68 2m

Package Details






The MH12SE package is very comparable to the “premium” P20iX in terms of extras, except it comes a standard thin cardboard box, colourfully printed with information on the light. Inside you will find the following:

  • Nitecore MH12SE flashlight
  • Nitecore-branded 5000mAh 21700 battery (NL2150)
  • 1×18650/2xCR123A battery holder
  • Tactical belt holster (NTH10)
  • Wrist lanyard
  • Pocket clip
  • USB-C charging cable
  • Spare O-ring
  • Manual

That’s a nice package, including everything you would need for the light. I particularly like seeing the belt holster, as that is always my preferred mode of carry (and very rare to see nowadays). This hard plastic model seems to hold the light securely, and allows for quick grab, pull and release.

Build


From left to right: LiitoKala 21700 (5000mAh), Fenix ARB-L21-5000U 21700 (5000mAh), Sofirm IF25A, Fenix E35 v3, Convoy S21E, Imalent MS03, Armytek Wizard C2 Pro Max, Acebeam E70, Nitecore P20iX, Nitecore MH12SE, Lumintop D3, Convoy M21F.








The MH12SE is a bit longer than most flashlights in this class, likely due to the use of an actual forward clicky switch. It has narrow head, and fits well into the bundled holster.  I find it fits and works comfortably in the hand – I don’t find it too long (although I do have large hands).

It’s great to see a forward tail clicky switch again – I’ve always had a fondness for this format. You use this clicky switch as your main switch for on/off operation and signaling, with a secondary electronic switch to cycles modes. Feel and traverse of the main switch is good, for both momentary (half-press) and clicked-on. The secondary switch is electronic, with a fairly typical feel.

Note that since the primary switch protrudes, tailstanding is not possible, and accidental activation is easy. So as always, I strongly recommend you keep the light stored locked out at the tailcap when not in use. A simple twist of the tailcap will do the job, thanks to the anodized screw threads. There is a side cut-out in the tailcap for the wrist lanyard, if you want to use it. The belt clip fits on securely, and comes off without leaving a mark. I believe the clip is intended primary for bezel down carry, but  the light could be carried the other way in a pinch.

The body is fairly smooth overall, but has a good number of rings and cutouts to help with grip. Knurling is not very aggressive – it could be enhanced, but its not unreasonable for a general purpose light. The light can roll fairly easily, but the flat cut-outs in the head help  a little bit with this (the clip would considerably, if you used it).

Anodizing looks to be very good quality, relatively matte in finish. It is advertised as type III (Hard Anodized), and I see no cause to doubt that. I didn’t notice any flaws on my sample.

As you can see above, there is a standard tailspring in the tailcap, and Nitecore uses a standard button-top 21700 cell in this light. This is an advantage over the P20iX, where the dual-switch tailcap design necessitates a custom cell. You can swap in another battery easily enough, and can charge the cell outside the light if you want. Of course, by default, you are expected to charge the battery right inside the light. There is a rubber plug in the head, across from electronic mode switch, that covers the integrated USB-C charging port (cover fits securely, but without too much resistance). I expect waterproofness to be reasonable, but wouldn’t recommend dunking the light in water.

As always, I find the physical build of the MH-series lights from Nitecore to be very good for general purpose use. I really like the bundled MOLLE-compatible holster here, that is a pretty rare accessory.


The SFT-40 emitter is ideal for producing a very throwy beam, thanks to its low profile and lack of dome – even when coupled with a small reflector like this. The glass lens has a mild AR coating, which I rather prefer. The aluminum bezel has some very minor crenelations, so you can tell if the light is on when headstanding.

There is a LED under the electronic switch in the head, which lights up when the light is in use (or charging).

User Interface

The MH12SE features Nitecore’s standard dual user interface (UI) design, referred to as  as Daily Mode and Tactical Mode.

Switching between them is easy (but not something you are likely to do by accident). Press and hold the electronic switch while the light is off, and then press the tail switch while still holding the electronic switch for another ~ 5 secs or so. At that point, the light will flash rapidly (one flash for Daily Mode, two flashes for Tactical Mode).

Simply defined, Daily Mode has 5 constant output levels (Ultralow, Low, Mid, High and Turbo, in sequence) plus three strobe modes (Strove, SOS, and Beacon). The light has mode memory (except for SOS and Beacon). Tactical Mode cycles in the reverse direction from highest to lowest for the 5 constant output modes and Strobe, and does not use memory – the light always comes back on in Turbo.

Let’s start with Daily Mode, then Tactical Mode.

Daily Mode, from OFF:

  • Partial depress Main switch: Momentary On in last memorized mode used
  • Single-click Main switch: Turns On in last memorized mode used (this includes strobe modes, if set)

Daily Mode, from ON:

  • Single-click Main switch: Turns Off
  • Press-and-hold Side switch: Activate strobe modes (Strobe > Beacon > SOS). Release the Side switch to choose the desired strobe. Click the Side switch again to return to the last mode used.
  • Single-click Side switch: Move up to the next constant output level (Ultralow > Low > Mid > High > Turbo).

Tactical Mode, from OFF:

  • Partial depress Main switch: Momentary On in Turbo (no memory)
  • Single-click Main switch: Turbo (no memory)

Tactical Mode, from ON:

  • Single-click Main switch: Turns Off
  • Press-and-hold Side switch: Strobe (only, no other blinky modes). Press the side switch again to return to the last mode used.
  • Single-click Side switch: Move down to the next lower constant output level (Turbo > High > Mid > Low > Ultralow).

Switch to/from Daily or Tactical Modes, from Off:

  • Hold down Side switch and single-click Main switch while continuing to hold down Side switch for ~ 5 secs (flashes once for Daily Mode, twice for Tactical Mode, and then turns on at start of constant output ramp for that mode).

Shortcuts:

None.

Mode memory:

Yes, but only in Daily Mode, and for all output levels (i.e., constant output modes and strobe modes).

Strobe/Blinking modes:

Yes; Strobe, Beacon and SOS.

Low Voltage warning:

Yes. There is a power LED indicator under the side switch in the head that remains lit while the flashlight is in use – and will flash every two seconds once the battery is more than 50% drained.

Lock-out mode:

Yes, but only by physically locking out the light at the tailcap.

Temperature regulation control:

Yes. This light features Nitecore’s proprietary “Advanced Temperature Regulation” (ATR) control. It should keep the temperature within a reasonable range.

Reviewer Comments:

This is reasonable dual physical/electronic switch interface, with a good number of options. Personally, I like Daily Mode with its memory feature – although I don’t like having to cycle through Strobe to get to Beacon, and would have liked to be able to jump to Ultralow or Turbo by a shortcut.

Circuit Measures

Pulse-Width Modulation (PWM):

There is no sign of PWM on any level, the circuit appears to be fully current-controlled.

It’s actually refreshing to see no high-frequency circuit noise – it isn’t visible to the eye, but it is something that I’m seeing more commonly on modern lights. Glad to see its absence here.

Ultra Lo:
Ultra Lo

Lo:
Lo

Med:
Med

High:
Hi

Turbo:

Looking good!

Strobe:
Strobe
Strobe
Strobe

Strobe mode oscillates between a 15 Hz and 16 Hz strobe, with two different pulse durations (switching every two seconds or so). Note that both strobes are unusual, as they spends more time in the on-state than the off-state on each cycle. It is certainly very disorienting.

SOS:
SOS

Beacon:
Beacon

Beacon mode flashes approximately once every 2 seconds or so.

Charging:

Like the P20iX, the MH12SE uses a single-current charging feature, with a very fast-charging 2.0A rate. I normally like to see a two-stage charging implementation. But it is hard to over-discharge the cell given that the light steps down and eventually shuts off as the cell drains.

Standby / Parasitic Drain:

There is no standby drain on this light, thanks to the physical clicky switch.

That said, I always recommend you lock the light out when not in use to prevent accidental activation. A single twist of the tailcap will lock out this light, thanks to the anodized screw threads.

Emitter Measures

This section is a new feature of my reviews, where I directly measure key emitter characteristics in terms of colour temperature, tint, and colour rendition. Please see my Emitter Measures page to learn more about what these terms mean, and how I am measuring them.

As explained on that page, since I am using an inexpensive uncalibrated device, you can only make relative comparisons across my reviews (i.e., don’t take these numbers as absolutely accurate values, but as relatively consistent across lights in my testing).

The key measures above are the colour temperature of ~5650K, and the significant positive tint shift (+0.0139 Duv) to green-yellow at this temperature.

For CRI (Ra), I measured a combined score of 67.

These values are well within the range for SFT-40-W emitters, and match my visual experience of this light.

Beamshots

All outdoor beamshots are taken on my Canon PowerShot S5 IS at f/2.7, 0.5 secs exposure, ISO 400, daylight white balance. The bend in the road is approximately 40 meters (~45 yards) from the camera. Learn more about my outdoor beamshots here (scroll down for the floody light position used in this review).

Click on any thumbnail image below to open a full size image in a new window. You can then easily compare beams by switching between tabs.



As you can see above, the beam pattern for the MH12SE is very throwy, as expected for a SFT-40 emitter. Indeed, compared to the SFT-40-equipped Convoy S21E, the MS12SE is even more focused for throw (and with less intense spill).

Testing Results

My summary tables are generally reported in a manner consistent with the ANSI FL-1 standard for flashlight testing. In addition to the links above, please see my output measures page for more background.

All my output numbers are based on my home-made lightbox setup. As explained on that methodology page, I have devised a method for converting my lightbox relative output values to estimated lumens. My Peak Intensity/Beam Distance are directly measured with a NIST-certified Extech EA31 lightmeter.

MH12SE Testing Results

ModeSpec LumensEstimated Lumens @0secEstimated Lumens @30 secsBeam Intensity @0secBeam Intensity @30secsBeam Distance @30secsPWM/Strobe FreqNoise FreqCharging Current <3VCharging Current >3VParasitic DrainWeight w/o BatteryWeight with Battery
Ultralow10.80.8---NoNo2.0 A2.0 ANo80 g151 g---
Low455454---NoNo2.0 A2.0 ANo80 g151 g---
Mid260320310---NoNo2.0 A2.0 ANo80 g151 g---
High1,0501,0001,000---NoNo2.0 A2.0 ANo80 g151 g5,6510.0139-
Turbo1,8002,1001,50048,600 cd35,400 cd376 mNoNo2.0 A2.0 ANo80 g151 g---
Strobe1,800-----16-20 HzNo2.0 A2.0 ANo80 g151 g---
Beacon1,800-----0.5z HzNo2.0 A2.0 ANo80 g151 g---
SOS1,800------No2.0 A2.0 ANo80 g151 g---

I know my lightbox tends to produce higher results than some, but there seems to be a pretty good concordance to the published specs. I like seeing ~0.8 lumen Ultralow mode – close enough to be considered Moonlight.

Beam distance measurement is very good, demonstrating significant throw (but not quite up to the level of the reported specs).

To see full testing results for all modern lights in my testing, check out my Database page.

Runtimes

As always, my runtimes are done under a small cooling fan, for safety and consistency. To learn more about how to interpret runtime graphs, see my runtimes methodology page.

Max

Hi

Med

Not surprisingly, given the small mass in the head, both Turbo and High ramp down to a lower ~800 lumen level fairly quickly. This is consistent with other compact lights that also can’t sustain super-high outputs for long.

The Convoy S21E with a SFT-40 is obviously the closest comparable to this light – and as you can see, the MH12SE has a noticeable output advantage over the S21E for equivalent runtime. This is an excellent result, showing excellent output/runtime efficiency.

The regulation pattern not as stable as I would like, with a “noisy” appearance at the highest two levels. But that is not as much of of an issue as it appears, since it not noticeable at physiological timescales. To demonstrate, here is a blow up of a period the Hi mode runtime during a period of maximal fluctuations:

Hi

While not perfectly flat, it is no more than a ~5% change in output over time, with a gradual transition (i.e., this change isn’t fast or significant enough to be noticeable by eye).

In any case, the MH12SE shows a good regulation pattern overall, with a series of step-downs to lower levels once the battery is almost drained.

Pros and Cons

ProsCons
Light has excellent output/runtime efficiency, at all levelsTurbo and Higher modes both ramp down to a reduced Hi level fairly quickly, due to heat.
Circuit shows good regulation overall, with thermally-mediated ramp down on Turbo/High, and step-downs as the battery is almost drained.The reduced Hi level shows a variable change in output (i.e., not completely stable).
Uses a dual switch design, with physical tailcap clicky for on/off.Has an very good "Ultra-low" level that could serve as a moonlight mode.
Good build quality and hand feel.

Overall Rating

Preliminary Conclusions

This MH12SE has performed very well in my testing. You get excellent overall output/runtime efficiency, with a reasonable set of output levels (including a <1 lumen level). The dual user interface – with a fairly standard set of levels and mode memory, and a “tactical” set – is well implemented with the dual physical clicky switch and electronic side switch. Build quality is solid, with decent hand feel. And it offers a surprisingly throwy beam in such a small light, thanks the SFT-40 emitter.

There are a few things to keep in mind however. Max output quickly settles down to ~800 lumens on both Hi and Turbo, due to low thermal mass of the light (so there are not as many discrete levels as first appears). The regulation is not as flat as I would like at this point either, but the fluctuations are not something you can see by eye (and efficiency is still excellent).

Like in my P20iX review, I like the dual user interface setup, especially coupled with the forward physical clicky switch. That is of course more of a personal preference – but it is helpful in a “tactical” light. And one advantage here is that a standard 21700 battery is used, which means you can swap in/out other cells, and charge outside the light if you prefer (although the in-light charging worked well, with a good charging rate).

At the end of the day, this is an excellent performer, with good ergonomics and build quality. I’m giving a half-star advantage over the P20iX – mainly for the standard battery – but either light is a strong contender for the class, it all just depends if you want throw (MH12SE) or flood (P20iX).

Acknowledgement

The MH12SE was provided for review by Nitecore. All opinions are my own however, and the light received the same rigourous and objective testing as all other lights that I have reviewed. At the time of review, this light retails for ~$100 USD (~$140 CDN).

Convoy S21E

The S21E is a popular light from the budget flashlight maker Convoy, and is powered by a single 21700 battery. It comes with a variety of emitters options, and features a decent user interface.

  1. Introduction
  2. Manufacturer Specifications
  3. Package Details
  4. Build
  5. User Interface
  6. Circuit Measures
  7. Emitter Measures
  8. Beamshots
  9. Testing Results
  10. Runtimes
  11. Pros and Cons
  12. Overall Rating
  13. Preliminary Conclusions
  14. Acknowledgement

Introduction

In my previous reviewing era, I stayed away from budget lights for the reasons I outlined here. But upon my return to reviewing, I’ve noticed a number of inexpensive brands seem to have good quality and consistency. So I thought it was time to start looking at some of the more popular budget models in the 1×21700 class.

Cue up Convoy, whose S21 series was up to its fifth iteration by last fall – the S21E – when I purchased these samples for testing. At the time, the S21E was available with a choice of three different emitters, so I picked them all up from the official store for comparison testing (although many more tint options are available). Specifically, these are ones with the standard “4 mode” circuit (which actually has constant output 5 modes, along with a continuously variable ramp).

I see there are a wider variety of anodizing colours available now, and a different battery than what came bundled with mine. But the specs remain the same, so your performance should match what you see below.

Manufacturer Specifications

Note: as always, these are simply what the manufacturer provides – scroll down to see my actual testing results.

FeatureSpecsSpecsSpecs
MakerConvoyConvoyConvoy
ModelS21ES21ES21E
EmitterNicha 519ASST40SFT40
Tint5000K (Hi CRI>90)6500K6500K
Max Output (Lumens)1,3002,4001,800
Min Output (Lumens)---
Max Runtime---
Max Beam Intensity (cd)---
Max Beam Distance (m)---
Mode Levels5 + Ramp5 + Ramp5 + Ramp
FlashingStrobeStrobeStrobe
Battery1x217001x217001x21700
Weight (w/o battery)88 g88 g88 g
Weight (with battery)168 g168 g168 g
Length116.4 mm116.4 mm116.4 mm
Head Diameter27.3mm27.3mm27.3mm
Body Diameter27.3 mm27.3 mm27.3 mm
WaterproofIPX4IPX4IPX4

Package Details

20221204_105843

Like many Convoys, the S21E can be purchased with any of a number of emitter choices and tints. Shown above are the Nichia 519A 5000K, Luminus SST40 6500K, and Luminus SFT40 6500K. But a wide range of 519A tints (from 2700K through 5700K) are possible, along with a limited number of Luminus tints (although not all options available for each emitter, nor at any given time on the store front).

The S21E is shipped in a simple cheap cardboard box, wrapped in thin bubble wrap. Inside, you will find the following:

  • Convoy S21E with removable pocket clip attached
  • Thin wrist lanyard, also attached
  • If you buy the version with a battery included, a thin filter pad is included to block contact during shipping

And that’s it. There is no manual or instruction sheet, so you’ll need to check out reviews like this to learn how it works and what all the features are. Minimalist to be sure, in keeping with the price.

Build

20230402_162025
From left to right: LiitoKala 21700 (5000mAh), Fenix ARB-L21-5000U 21700 (5000mAh), Sofirm IF25A, Fenix E35 v3, Convoy S21E, Imalent MS03, Armytek Wizard C2 Pro Max, Acebeam E70, Nitecore P20iX, Nitecore MH12SE, Lumintop D3, Convoy M21F.

Note: in all photos below, the sequence from left to right (or top to bottom), are always the Nichia 519A, SST40, and SFT40 emitter versions. Also note that the SST40 version was bought in early fall 2022, and the other two were a couple of months later.

20221204_105042
20221204_105104
20221204_105126
20221204_105156
20221204_105423
20221204_105454
20221204_105519
20221204_105544

The S21E is a minimalist, compact build – but seems very well made.

There is a large switch cover over the side-mounted electronic switch. Feel is good, with smooth action. There is a red and a green LED underneath, to show you the charge status when charging (see below).

There is a small spring on the positive contact terminal in the head, so flat top cells can easily be used. Tailcap is flat with a standard spring and retaining ring. Note that my earlier SST40 sample (middle above) came with a stiff silver-coloured tail spring – that applied another enough pressure to dent the positive battery terminal against the head spring. Later specimens (left and right) came with gold-coloured springs than aren’t as stiff – and so, no denting. This also like reflects the thinner metal on the LiitoKala cells.

As an aside, I’m actually impressed to see the rapid correction of this design issue – especially in a budget build. That said, I did notice a batch issue with lens, which I will explain below.

There is an integrated USB-C charging port on the head of the light, across from the switch, under an attached rubber cover. Cover fits well enough to make me think the light is water-resistant, but less so than more expensive offerings in this class (and so, I wouldn’t recommend immersing it in water).

The light doesn’t have knurling per se, but rather a series of cut-outs along with the concentric circle “reeling.” While serviceable, this can be slippery in practice – so I recommend you leave the removable pocket clip attached to help with grip. The pocket clip attaches firmly. It is not reversible, but due to the design can be used for both upward and downward carry (although may be a bit tight, depending on what you want to clip it to).

Anodizing looks to be decent quality, in matte finish (I presume it is only type II, given you can get the light in a variety of colours). Tailcap screw threads are anodized, so you can lock out the light by a twist of the tailcap. I haven’t shown it above, but you can unscrew the head from the body too (screw threads there are not anodized there).

Thanks to the spring in the head, any regular-sized 21700 cell (without an integrated USB-C charger) should fit and work in the lights. You are best sticking with flat-top cells though, as longer cells (i.e., with a button top) may be too tight given the relatively short body.

20221204_105232
20221204_105257
20221204_105319
20221204_105342
20221204_105951

The Nichia 519A comes with a lightly textured reflector, while the Luminus models come with a smooth reflector. Reflectors are relatively shallow, and really seem to be designed best for the SST40 emitter (the SFT40 emitter has quite a few bright rings in its outer spillbeam, for example).

Note that my Nichia 519A and SFT40 samples both show a noticeable amount of purple fringing on the periphery of the spillbeam, due to a heavy purplish AR coating on the lens of those samples (the earlier SST40 sample lens has a milder greenish AR coating, which doesn’t affect the beam as much). Scroll down for beamshots, but I don’t find this purplish AR coating to be as noticeable or a problem on the Nichia model, likely due to the warmer tint and smoother beam profile. The AR tint difference may have been a batch effect of that particular point in time, because I have seen a SST40 model purchased more recently that has the lighter greenish AR coating.

The bezel is stainless steel, and is smooth without crenelations. So you may not be able to tell if the light is on when it is headstanding. The head opens easily at the bezel ring (i.e., no thread locker), and the lens and reflector come right out for easy access to the emitter. I am glad to note an o-ring on both the underside of the lens (toward the reflector) and on the bezel ring itself. This reassures me as to water-proofness.

Overall, I find this to be a very decent quality build – nothing flashy, but serviceable and much better than I expected for the price. Note that this is where having purchased 3 separate samples (over time) to evaluate is important, as I have found in the past that one of the issues with budget lights can be inconsistency. It’s good to see them all equally well made overall, and showing at least one incremental improvement over time (i.e., that prompt revision to a less stiff tail spring). But the lens AR coating issue, which appears to have been limited to a particular intermediate batch, shows that you may still have issues there.

User Interface

The S21E driver is a lot more advanced than I would have expected for a budget offering. It has a choice of two distinct multiple-output mode sets you can select: one with a smooth ramp in output from min to max, and one with four discrete steps (1%, 10%, 40%, 100%/Turbo) plus a 0.2%/Moonlight level. Also available is a “Tactical” mode which only has the Turbo level. A strobe mode is also available, along with some other bonus features.

So, let’s go through the user interface in detail:

From OFF:

  • Press and Hold: Moonlight
  • Single click: Turns on to the memorized brightness level
  • Double click: Turbo
  • Triple click: Strobe
  • 4 clicks: set to Tactical mode (i.e., only momentary 100% brightness)
  • 5 clicks: Voltage check. The light will blink out the voltage to one decimal place, first by the main volt, then by the decimal point (e.g., 3 blinks, a pause, and five more blinks would mean 3.5V).
  • 6 clicks: Switch between ramping mode and stepped mode
  • 10 clicks: Electronic lock out. Click for another 10 times to re-activate the light. Note that I suggest you simply lock the light out by a twist of the tailcap instead.

From ON:

  • Press and Hold (in Ramping mode set): Ramp up to 100%/Turbo. Press and hold again to ramp down to 0.2%/Moonlight. Release at any time to select the desired level. Note that when you restart the ramp after selecting a level, it reverses direction on the next press and hold.
  • Press and Hold (in Stepped mode set): Step up to next level (4 main levels on the sequence, Moonlight is not on the main sequence). Press and hold again to step down in levels.
  • Single click: Off
  • Double click: Turbo
  • 3 clicks: Strobe
  • 5 clicks: Voltage check
  • 6 clicks: Switch between ramping mode and stepped mode

Shortcuts:

  • To Moonlight: Hold from off
  • To Turbo: Double-click from any mode except Tactical
  • To Strobe: Triple-click from any mode except Tactical

Mode memory:

Yes. The S21E will memorize any brightness level except for Moonlight and Strobe.

Low voltage warning:

Yes. The light will drop down to ~1% output and the button will blink red before eventually shutting off at ~3V. Note that it can run for a very long time at this level before shutting down.

Reviewer Comments:

This is a very impressive interface – surprisingly versatile, but also very easy to use (i.e., very intuitive). Hand the light to someone, and it wouldn’t take them long to get used to it, the modes make a lot of sense. Switching between ramping and stepped mode sets is a bit peculiar with the six clicks, but it’s not like it’s something you will want to switch between often anyway.

Note that the highest output modes step down automatically after a period of time (and heat build up – scroll down for runtimes). And while I’m glad to see the “Moonlight” mode here, it is not actually low enough to be what I would consider a true moonlight (see Testing Results for more info).

Circuit Measures

Pulse-Width Modulation (PWM):

There is no sign of PWM at any level – the lights appear to be current-controlled. However, I did detect an oscillating noise pattern on several of the levels, include Turbo, as shown below.

Turbo/100% (Nichia 519A, SST40, SFT40)
S21E-Nichia-100S21E-SST40-100S21E-SFT40-100

As you can see, the pattern is variable in intensity, and at a high frequency (~3-6kHz). But rest assured it is not something that you can see visually. It is even more detectable at the higher intermediate outputs, as shown below.

Step 40% (Nichia 519A, SST40, SFT40)
S21E-Nicha-40S21E-SST40-40S21E-SFT40-40

Here is a blow-up of one of the 40% levels, which clearly shows a simple sine-wave oscillation (i.e., no PWM here). Some people call this a saw-tooth noise pattern.

40% SS40 Zoomed in
S21E-SST40-40-Zoom

Still present at the 10% output level:

Step 10% (Nichia 519A, SST40, SFT40)
S21E-Nichia-10S21E-SST40-10S21E-SFT40-10

But it seems to disappear by the lower outputs, as shown below for both the stepped and ramp outputs – but that may just be because the output is too low for my oscilloscope to detect.

Step 1% (Nichia 519A, SST40, SFT40)
S21E-Nichia-1S21E-SST40-1S21E-SFT40-1

Ramp Lo (Nichia 519A, SST40, SFT40)
S21E-Nichia-LoS21E-SST40-LoS21E-SFT40-Lo

Again, none of the above is an issue in use. I am simply including the scope readings for completeness.

Strobe:

Strobe (Nichia 519A, SST40, SFT40)
S21E-Nichia-StrobeS21E-SST40-StrobeS21E-SFT40-Strobe

Strobe frequency is a very consistent fast 10.1 Hz, which most would consider a tactical frequency.

Charging:
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20221204_105715

Note that the red/green LEDs are very bright when charging.

Charging rate for the Nichia 519A, SST40, SFT40:
S21E-Nichia-charging1
S21E-SST40-charging2
S21E-SFT40-charging1

The S21E has a single high-current charging rate of ~2.0A-2.1A, as shown for the 3 specimens above.

I normally like a two-stage charging feature (i.e., with a lower charging rate for when cells are heavily discharged). But the light output drops down to a super low mode when the battery is running low, and big red button flashes incessantly, warning you to shut down. In fact, it is actually very hard to get the cell below ~3.0V in this light. As such, this is reasonable compromise to stick with a single high charging rate.

Standby / Parasitic Drain:

I measured the standby current across the 3 samples at a negligible 31.5 uA, 30.5 uA, and 31.0 uA.

This is nice and ultra-low standby current, and is not a concern for draining the cells. However, I always suggest you lock the light out when not in use to prevent accidental activation (and cut the negligible standby drain in this case). A single twist of the tail will lock out this light, thanks to the anodized screw threads.

Emitter Measures

This section is a new feature of my reviews, where I directly measure key emitter characteristics in terms of colour temperature, tint, and colour rendition. Please see my Emitter Measures page to learn more about what these terms mean, and how I am measuring them.

As explained on that page, since I am using an inexpensive uncalibrated device, you can only make relative comparisons across my reviews (i.e., don’t take these numbers as absolutely accurate values, but as relatively consistent across lights in my testing).

S21E Nichia 519A:

The key measures above are the colour temperature of ~4330K, and a slight negative tint shift (-0.0008 Duv) to rose at this temperature.

For CRI (Ra), I measured a combined score of 94.

These results are consistent with neutral-white Nichia 519A emitters, and match my visual experience of this light.

S21E SST40:

The key measures above are the colour temperature of ~5350K, and the very noticeable positive tint shift (+0.0166 Duv) to green-yellow at this temperature.

For CRI (Ra), I measured a combined score of 50.

These results are consistent with high output Luminus SST emitters (although CRI is a bit low on my sample), and match my visual experience of this light.

S21E SFT40:

The key measures above are the colour temperature of ~5660K, and a noticeable positive tint shift (+0.0136 Duv) to green-yellow at this temperature.

For CRI (Ra), I measured a combined score of 65.

These results are again consistent with high output Luminus SST emitters, and match my visual experience of this light.

Beamshots

All outdoor beamshots are taken on my Canon PowerShot S5 IS at f/2.7, 0.5 secs exposure, ISO 400, daylight white balance. The bend in the road is approximately 40 meters (~45 yards) from the camera. Learn more about my outdoor beamshots here (scroll down for the floody light position used in this review).

Click on any thumbnail image below to open a full size image in a new window. You can then easily compare beams by switching between tabs.



Testing Results

My summary tables are generally reported in a manner consistent with the ANSI FL-1 standard for flashlight testing. In addition to the links above, please see my output measures page for more background.

All my output numbers are based on my home-made lightbox setup. As explained on that methodology page, I have devised a method for converting my lightbox relative output values to estimated lumens. My Peak Intensity/Beam Distance are directly measured with a NIST-certified Extech EA31 lightmeter.

S21E Testing Results

EmitterModeSpec LumensEstimated Lumens @0secEstimated Lumens @30 secsBeam Intensity @0secBeam Intensity @30secsBeam Distance @30secsPWM/Strobe FreqNoise FreqCharging Current <3VCharging Current >3VParasitic DrainWeight w/o BatteryWeight with Battery
Nicha 519AMoon 0.2%-1010---NoNo2.0 A2.0 A31.5 uA89 g154 g
Nicha 519A1%-1919---NoNo2.0 A2.0 A31.5 uA89 g154 g
Nicha 519A10%-230230---No4.4 kHz2.0 A2.0 A31.5 uA89 g154 g
Nicha 519A40%-550540---No5.9 kHz2.0 A2.0 A31.5 uA89 g154 g
Nicha 519ATurbo 100%1,3001,3001,25011,510 cd10,550 cd205 mNo5.3 kHz2.0 A2.0 A31.5 uA89 g154 g
Nicha 519AStrobe------10.1 HzNo2.0 A2.0 A31.5 uA89 g154 g
SST40Moon 0.2%-1616---NoNo1.65 A2.0 A30.5 uA87 g153 g
SST401%-2929---NoNo1.65 A2.0 A30.5 uA87 g153 g
SST4010%-340340---No4.9 kHz1.65 A2.0 A30.5 uA87 g153 g
SST4040%-750740---No6.6 kHz1.65 A2.0 A30.5 uA87 g153 g
SST40Turbo 100%2,4002,0502,00027,300 cd26,000 cd322 mNo6.9 kHz1.65 A2.0 A30.5 uA87 g153 g
SST40Strobe------10.1 HzNo1.65 A2.0 A30.5 uA87 g153 g
SFT40Moon 0.2%-1313---NoNo2.1 A2.1 A31 uA90 g156 g
SFT401%-2626---NoNo2.1 A2.1 A31 uA90 g156 g
SFT4010%-280280---No4.5 kHz2.1 A2.1 A31 uA90 g156 g
SFT4040%-650640-No6.0 kHz2.1 A2.1 A31 uA90 g156 g
SFT40Turbo 100%1,8001,7501,70041,400 cd37,500 cd387 mNo3.2 kHz2.1 A2.1 A31 uA90 g156 g
SFT40Strobe------10.1 HzNo2.1 A2.1 A31 uA90 g156 g

To see full testing results for all modern lights in my testing, check out my Database page.

Runtimes

As always, my runtimes are done under a small cooling fan, for safety and consistency. To learn more about how to interpret runtime graphs, see my runtimes methodology page.

S21E-Max

S21E-Hi

S21E-Med

As you can see above, the S21E circuit is well regulated, with thermal-mediated step-downs at the higher levels. Note that output tends to rise a little bit near the end of the runs on these levels, before stepping down to the low output.

Here is an expanded view of the max runtime graph, so that you can see the first few minutes with better resolution:

S21E-Max-expanded

Overall efficiency is quite good for each given emitter type. I’m taking the budget cell’s 5000mAh rated capacity as face value here (always a stretch for budget cells), but the SST40 specimen shows nearly comparable efficiency to brand name lights, which is impressive. So this suggests the overall efficiency of this circuit is high.

Pros and Cons

ProsCons
Very good current-controlled efficiency for each emitter type, across all modes/levels.Stepped mode spacing is not ideal, and Moonlight mode is too bright to qualify as a true moonlight.
Great feature set with both ramping and discrete output levels, including Turbo and Moonlight modes.Light heats up quickly on Turbo, given low thermal mass.
Nicely balanced beam profile for SST40 and Nichia 519A models.Significant purple fringing at the edge of the spillbeam on two samples, due to a batch of heavy AR coated lens.
Very compact build, quite petite for the class.Green/Red LEDs under the switch covers are very bright, and the low-voltage warning flash can be distracting.
Optional included high-capacity battery.Older models came with a very stiff tail spring that caused denting of LiitoKala cells (seems resolved on more recent versions).

Another minor issue I noted is the ramping speed is rather quick. But given how few lights actually give you a choice of a continuous ramp option, this is hardly a complaint!

Overall Rating

Preliminary Conclusions

My new rating system above is based solely on the features of the light, without taking cost into account. And so, given the very low cost of these lights, this is a really impressive showing.

I’m particularly impressed by the performance and versatility of the circuit, and the option for both discrete stepped levels and a continuous ramp. Yes, the discrete levels are not really well spaced, and the ramp is a bit fast, but these seem like relatively minor quibbles. It is frankly surprising to see such a versatile circuit in a budget light, with such good regulation and efficiency.

Charging performance was very good under the circumstances, with a negligible standby drain. All said, this is quite an impressive set of of circuit features for the price. It’s definitely few frills in terms of extras, but it has what you need where it counts.

Physically, the light is a very good build, quite serviceable with decent hand feel and use. There is not a lot of mass however, so it does heat up quickly. And of course, as is often the case with budget lights, you can get variability in components over batches (i.e., the too-strong tail spring on my SST40 sample, the heavy purple AR lens coating on the other two, etc.). So that is one thing you will have to accept in a budget brand.

Beam pattern is reasonably good for all three emitters. That said, the rather small improvement in throw of the SFT40 over the brighter overall SST40 doesn’t seem worth it to me. And the small reflector here seems to be introducing brighter defined rings in the periphery of the SFT40 spillbeam (which is accentuating the purple fringing of the AR coating on that particular sample). I think a light with a larger head/reflector would really be necessary to take best advantage of the SFT40 emitter. So I recommend you stick with the SST40 or Nichia 519A in this series, in your preferred colour temperature (and very nice that they offer that).

I’m glad I decided to pick these up to test. Based simply on their own merits, they are worthy contenders to consider in the 1×21700 space. When you factor in their incredibly low-cost budget price, I’d say these lights are well recommended (at least the Nichia 519A and Luminus SST40 versions).

I’m looking forward to seeing how other budget lights perform.

Reviewer’s Additional Comment: A new model in the S21-series has just come out, the S21F. However, this is a significant build change from the earlier S21-series lights, with a blended multi-emitter design. The S21E remains the most advanced version of the compact, single-emitter 1×21700 light from Convoy.

Acknowledgement

The S21E samples were personally purchased from the Convoy store of Aliexpress in the fall of 2022. At the time of review, these lights retail for ~$30 USD (~$40 CDN) with a bundled battery.