This is a Surefire Flashlight known as the M640, model M640V-BK-PRO.
SureFire makes some of the finest Suppressors" Flashlights" Weaponlights; Lasers" Ear Protection; Firearm Components" and Tactical equipment on the market today.
Features:
350 Lumen White Light
120mW Infrared Light
1913 Picatinny Mount
M-LOK Mount
On/Off Tail cap