Body: The battery tube makes up the other half of the M2 and has a rectangular shape since batteries are housed in parallel alignment. The narrow faces of the battery tube have shallow ribs which provide adequate grip while the wide faces have horizontal lines running the length of the battery tube. A battery magazine is housed on the inside of the battery tube which can hold either 2x 18650 or 4x CR123. When using in 4x CR123 configuration, the included CR123 holders come in handy. The battery magazine feels secure and is enforced by four aluminum bars connecting the PCB on the front and rear ends. Battery contact on the battery holder are also gold-plated for improved electrical conductivity. Towards the rear end is a wide rectangular slot for lanyard attachments. The M2 also comes with an option to install a push button switch assembly if desired. This involves removing four screws from the rear of the battery tube and is easy enough to perform. When used with the push button switch, the activation of the light is controlled by the switch while mode changes are controlled by the rotary ring on the head. The switch mechanism has average tension and travel, providing a tactile clicking feedback when engaged. It is a forward push button switch so momentary activation is possible. However do take note that with the push button switch installed, the M2 is not able to tail stand. As of this writing, there are some water resistance issues which are being addressed by EagleTac. Since the M2XC4 comes with a limited lifetime warranty, they will send you the required components for the fix.

Bezel/Head:There are currently three versions of the M2 available from EagleTac, the one reviewed here is the M2XC4 which uses three R2 binned XR-E LED's with a cool color temperature. The head makes up a significant part of the light and feels very solid and noticeably heavier than the battery tube. Right up the front is stainless steel crenellated bezel which is easily removable if you wish to use the M2 without the bezel. Behind this sits a multi-coated glass lens and an o-ring for water resistance. The three LED's are focused by three segmented reflector cups with smooth surface finish. All three reflectors are well polished with no noticeable flaws. Two of the LED's are well centered while one, at the bottom right as shown in the image here, is just slightly off relative to the reflector cup. The exterior of the head has a simple cylindrical design. Towards the front end is a band of knurling which provides grip when unscrewing the head for battery changes. Towards the rear end of the head is a polycarbonate rotary ring which controls the activation and mode switching of the light. This ring has a rubber coating which gives it's surface a nice feel and better grip when twisting. By default, both switching on and changing or modes are done by simply twisting this rotary ring. I noticed that the amount of twist required to change between Off, Level 1 and 2 is slightly more than when switching to Level 3, 4 and Strobe mode. Threads on the head are well machined and anodized. They're also very thick and mate well with threads on the battery tube perfectly well. The battery contact on the rear end of the head are gold-plated and designed well providing good electrical contact.

Output:The M2XC4 has five output modes in the following order:The M2C4 which uses a P7 LED outputs a maximum of 900 lumens as compared to the 800 lumens of the three R2 binned XR-E LED's used in the M2XC4. The beam profile produced by the M2XC4 has a distinct triangular shaped hotspot with a bright corona. The spill beam is also very bright and should provide more than adequate peripheral illumination. There are some noticeable artifacts in the area around the corona as is common with most light using smooth reflector cups, though they don't really affect practical usage. The color temperature produced by this review sample was a neutral while, slightly cool when compared to sunlight white. Regulation is maintained well on all levels, even at the maximum brightness level. Relative to the amount of light produced, runtime is above average. As you can see from the runtime graphs below, running on CR123 produces practically identical output brightness, and only a little more runtime. As such, it's definitely more worth while to run on rechargeable 18650 cells.

Runtime:

Photo Gallery

Body Tube(front)	Body Tube(side)	Body Tube(rear)

Conclusions: The Good - Fit and finish are very well done. Rotary ring provides easy selection of output modes. Huge amount of light output with respectable runtime and excellent regulation. Comes with accessories for carrying, especially useful for a light this size.
The Bad - No locking position on rotary ring could result in accidental activation, although this can be negated by using the optional switch assembly. Large size and weight might not be comfortable for everyone.
The Relative - Light produced has a cool color temperature. Optional forward push button switch allows for momentary activation. Is able to tail stand without push button switch assembly.

Quick Facts Table: