The head of the Bolt 2L houses a Lumileds Luxeon K2 emitter. The entire head is sealed onto the battery tube and is not removable. Its advertised that the head is impact resistant, and so is the lens. Seems like the lens is made of a polycarbonate material, it doesn't seem to have any AR coating from what I see could. Inside the head is a smooth reflector which is well aligned with the emitter. The exterior of the head has a hexagonal design which serves as an anti-roll feature. Finishing on the exterior is very well done, machining is nice and smooth. Anodized coating is consistent as well, no marks or blemishes to be found.

The battery tube is a and has a hexagonal rubber sleeve which provides good grip. The rubber grip feels a little sticky to me. Personally, I would have preferred rubber which has a dryer feel. Other than the rubber grip, the battery tube is pretty plain and simple with no additional aesthetic design elements other than the Inova branding. Do take note that the batteries should be inserted "-" end first, and not the usual "+" end first. Inside, the battery tube is clean and smooth. Now, moving on to the tail cap. The Bolt 2L uses a momentary switch, but its not a click push button. For constant on operation, you'll need to twist and tighten the tail cap down. Inside the tail cap is the momentary mechanism. Its loose and rattles when the tail cap is removed, but when screwed onto the battery tube, the "-" contact spring's tension sits it securely in place. Threading is well done and I didn't experience any cross-threading at all. However, I find the threads were cut slightly fine which sometimes makes it difficult to align. On the external side of the cap there's a band of diamond textured knurling which provides sufficient grip for battery changes. Finally, at the rear end of the cap is the rubber button which is used for momentary on. There is no tactile feel when the light is turned on and there's no clicking sound at all. The Bolt 2L is advertised as water resistant but not waterproof.

The beam profile is of a medium spot, with some slight rings around the hotspot. Tint is on the warm side, and slightly yellow. Output is regulated well, but compared to the newer XR-E emitters, the K2 isn't as bright or efficient when it comes to battery life.

The Good - Solid construction and reliable momentary switch mechanism.

The Bad - Runtime is quite short considering its output intensity.

The Relative - Beam tint is a warm yellow. Slight ring artifacts in beam profile.

Head (front view).

Body (side view).

Battery tube (rear view).

Tail cap (front view).

Tail cap (side view).

Tail cap (rear view).