Eagletac M3C4 Cree XM-L (2x18650) Review: COMPARISONS, BEAMSHOTS, RUNTIMES, etc.

Originally posted: February 4, 2011

Warning: even more pic heavy than usual :sweat:

Eagletac has recently released a new member of the M3C4 family Ė one containing the new Cree high-output XM-L emitter. For a comparison to other M3C4 lights, please see my original M3C4 review here or the revised M3C4 SST-50 review.

Common Specs for M3C4 Series:

M3C4 XM-L Specifics:

The light hasnít changed appreciably on the outside. Packaging also hasn't changed from my earlier reviews. Included with the light are extra o-rings, wrist lanyard, warranty card and manual, primary battery holders, clicky-switch battery carrier, diffuser (swappable with the removable bezel ring) and a good quality nylon case that fits the light well.

From left to right: AW Protected 18650, M3C4 XM-L, M3C4 SST-50 (OP), Thrunite Catapult V2 XM-L, Sunwayman M40C, JetBeam M1X V2.

M3C4 XM-L: Length: 164mm, Width: 61mm (bezel), Weight: 348.0g
M3C4 SST-50 SMO-Deep: Length: 165mm, Width: 61mm (bezel), Weight: 354.2g
M3C4 SST-50 OP: Length: 158mm, Width: 61mm (bezel), Weight: 334.7g

Bezel diameter has not changed - the bundled diffuser and optional colored filters still fit as before. The M3C4 XM-L has basically the same dimensions as the newer M3C4 SST-50 with the deep and smooth reflector, although the XM-L version is slightly lighter.

The body internals are the same, so please see my original M3C4 review for additional detailed pics, and a more thorough discussion of the build.

Like other members of the M3C4 family, the light features anodized screw threads, allowing for head lock-out.

The lights come in the two types of type III anodizing (dark gray or black Ė black shown here). Regardless, the plastic control ring and tailcap cover are made of black plastic. Anodizing quality is top-notch on my samples. There is plenty of ridge detail to help with grip, plus some decent knurling on the head. Lettering is sharp and clear, bright-white against the dark background.

As before, the top of the battery handle still has four Phillips-head screws holding it to the battery tube portion. I would prefer that this were a single piece of aluminum Ė I recommend you periodically check these screws to make sure they donít loosen up and compromise water-resistance of the battery handle.

No changes to the battery carrier. Note that flat-top high-capacity cells may not work in the carrier, as the plastic contact ring around the positive terminal is slightly raised. You can use CR123A cells with or without the included plastic holder.

The M3C4 series lights use small hex screws at the tail end of the battery tube. The included Allen key may be a bit small for some of the screws (i.e. you may need to find another similarly sized tool). Be very careful not to strip any of these screws when changing the tailcap - it can happen easily. If you encounter any resistance at all, back off and try again, or try a different screw (there are extras included).

For more on this potential issue, see my original M3C4 review and the discussion threads that followed.

(M3C3 SST-50 SMO-Deep on the left, M3C4 XM-L on the right)

As you can see, the new XM-L has a similar depth reflector as the SST-50 SMO-Deep. However, the XM-L version seems to be very slightly textured. I guess you could call it Light-Orange-Peel (LOP), but it really just looks like a slight haze over a SMO reflector (VLOP? :laughing:).

The opening is the same, so the smaller die-size of the XM-L is very apparent. The white plastic disc surrounding the die is being reflected in most of the reflector shots above.

For examples of what the optional YRGB colored filter kit (yellow, red, green, blue) and bundled diffuser look like on the earlier M3C4 lights, please see my original M3C4 review.


Here are some up-close shots comparing to other relevant lights. All lights are on 2xAW protected 18650, about ~0.75 meter from a white wall (with the camera ~1.25 meters back from the wall). Automatic white balance on the camera, to minimize tint differences.

The revised SST-50 SMO-Deep version is listed as "Rev" in the beamshots below.

Ok, so the M3C4 XM-L definitely throws furthers than the M3C4 SST-50 SMO-Deep. This is not surprising, given the smaller die size of the XM-L (i.e. easier to focus to a point). Scroll down for more detailed output/runtime comparisons.

Tint on my XM-L sample seems slightly on the warm (yellow-green) side of Cool White.

I've recently updated my 100-Yard Outdoor Beamshot Round-up, including the latest XM-L lights. Check out that round-up thread for more details on the testing method, plus higher quality JPEG images of all lights. For now, here is an animated GIF of relevant XM-L/SST-50 comparisons:

Key point above is that the M3C4 XM-L throws further than the M3C4 SST-50. It actually throws similar to the Olight M31 SST-50 (which has a much larger reflector). The new Thrunite Catapult V2 XM-L is more focused for throw, though.

User Interface

UI is unchanged. To turn the light on, turn the control ring clockwise (with the light pointed away from you). The light will proceed out of Standby and through Moonlight, Lo, Med, Hi and Turbo in sequence.

To access strobe, rapidly switch from Turbo to Standby and back to Turbo again. This will replace Turbo with Strobe. Do this switch again to advance to Beacon, and again for SOS (note the manual has Beacon/SOS order reversed). Do it once more to return to standard output modes with Turbo.

Alternatively, you can loosen the head (or click off the optional clicky switch) to break the connection to the battery carrier and fully shut off the light. This also restores the standard output modes upon re-activation.

Note that the light moves through the output levels in a gradual fade into each level over ~1sec or so as you turn the ring (i.e. you donít see a sharp jump/drop in output).

With the forward clicky switch module installed, the light can be turned on in any mode by the switch (with the control ring controlling the output level as before). There is no standby current with the clicky switch in the off position.

Parasitic Standby Drain

The M3-series lights have a parasitic standby drain. I measured it on my M3C4 XM-L at 1200uA, which is very similar to what I got on the original M3C4 SST-50 (i.e. 1170uA). That would translate into 76 days before two fully charged 2200mAh batteries would be completely drained. :caution: I therefore recommend you store the lights with the head locked-out, or use the optional clicky switch battery carrier. There is no standby current with the switched clicked in the off position.


All M3C4 lights appear to be fully current-controlled at all levels (so no PWM). :twothumbs


Strobe is unchanged at ~7.8Hz.

Beacon is a slow strobe, again unchanged at ~1.8Hz freq.

Testing Method: All my output numbers are relative for my home-made light box setup, a la Quickbeam's flashlightreviews.com method. You can directly compare all my relative output values from different reviews - i.e. an output value of "10" in one graph is the same as "10" in another. All runtimes are done under a cooling fan, except for any extended run Lo/Min modes (i.e. >12 hours) which are done without cooling.

I have recently devised a method for converting my lightbox relative output values (ROV) to estimated Lumens. See my How to convert Selfbuilt's Lighbox values to Lumens thread for more info.

Throw/Output Summary Chart:

Effective November 2010, I have revised my summary tables to match with the current ANSI FL-1 standard for flashlight testing. Please see http://www.sliderule.ca/FL1.htm for a description of the terms used in these tables.

As you can see, the M3C4 XM-Lís peak center-beam throw has increased considerably from the earlier SST-50 model (even the SMO-Deep).

Note that the lowest output level (Moonlight) is about typical on my XM-L sample. My M3C4 SST-50 SMO-Deep was abnormally low, and has been sent back in for re-tuning

Output/Runtime Comparison

Note: Effective January 2010, all CR123A runtimes are now performed on Titanium Innovations batteries. You can compare the performance of these CR123A cells relative to the Duracell/Surefire cells used in my earlier reviews here.

Hereís how the new M3C4 XM-L compares to the earlier SST-50 SMO-Deep and SST-50 OP versions:

As you can see, output has increased at all levels on the XM-L version, and there's typically a slight runtime advantage as well. Clearly, the M3C4 XM-Lís emitter is more efficient than the two SST-50 samples. :thumbsup:

And hereís how it compares to other lights in its class: (note the M3C4 XM-L is in red in the runtimes below).

The new XM-L lights seem to have an advantage over the earlier SST-50 and MC-E-based lights in terms of overall output and runtime efficiency. :thumbsup:

Note that I do not recommend running high-output lights on Max output with 4xCR123A. The batteries can quite hot in this arrangement.

Potential Issues

The same issues from my earlier M3C4 reviews apply. The tailcap hex screws seem somewhat variable in size, and may be stripped when trying to screw down. Use extreme caution when switching to or from the clicky tailswitch.

Standby parasitic drain is still very high for the whole M3C4 series Ė enough to fully drain a pair of 2200mAh 18650s in less than 3 months. I recommend you store the lights with the head locked out (or with optional clicky battery carrier in the clicked off position).

Flat-top 18650 cells may not work in the battery carrier, due to the raised plastic ring around the positive contact plate.

As with many lights of this class, the light is heavily driven on Max - so I recommend you run it in 2x18650 configuration in this mode. 4xCR123A is possible on Max, but not recommended for long periods of time (i.e. the batteries can overheat).

Preliminary Observations

As mentioned in my original M3C4 review and the revised M3C4 SST-50 review, the M3C4 build represents a number of nice upgrades from the earlier M2-series lights. The Cree XM-L emitter adds yet another powerhouse model to the line-up.

I think it was a smart move for Eagletac to revise the M3-series with a deeper smooth reflector for the SST-50 and XM-L models (the XM-L reflector seems ever so slightly textured, but could generally be considered smooth). To put it simply, the move to XM-L adds an extra ~25% max overall output (estimated lumens) and ~30% more throw (as measured by beam distance), as compared to the SST-50 version with the smooth deep reflector. :thumbsup:

Most users here seem to prefer more throw in these high-output lights, and the M3C4 XM-L certainly does an admirable job in that department (i.e. it slightly out-throws the larger-reflector M31 SST-50). Plus you always have the bundled diffuser if you want more flood. :) As an aside, donít get fooled by raw lux at 1m values. Center-beam lux is a non-linear scale (i.e. drops with distance according to an inverse square law). Beam distance is the appropriate measure to compare the ďthrowĒ of lights.

Along with greater output, the XM-L also seems to be more efficient than the SST-50 emitters used in the other M3C4 samples. As you can see in the runtimes above, at all levels the XM-L consistently exceeds both in output and/or runtime. :thumbsup:

Everything else about the build remains consistent with the revised M3C4 SST-50 I reviewed a few months ago. Please see that review, and my original M3C4 review for a greater discussion of the build design.

I expect these new XM-L-based lights to be quite popular in the high-output, 2x18650 class of lights. :)


All M3C4 lights were provided for review by Eagletac.

To follow the online discussions for this review, please see the full review thread at CPF.

Return to the master review list (at flashlightreviews.ca).

For a list of all my CPF flashlight reviews in chronological order by battery type (direct link to CPF), please see here:
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