Adjustable Rail: The weapon light fits Picatinny rails ( MIL-STD-1913) and Glock sized rails weapon guns. Rail grip clamp system securely attaches/detaches quickly and safely with no tools and without putting your hands in front of muzzle. Super Bright Gunlight: 208m beam up to 1200 lumens. It is much brighter than most other similar models pistol light. Momentary/Constant Switch: Rotary switch to turn left side to get momentary mode. To avoid exposing your position, "Momentary" mode would not stay, the switch will spring back immediately. Rotary switch to turn right side to get constant modes. Reliable, Efficient&Sturdy: Handgun flashlight is machined aluminum sealed construction with black anodized finish, impervious to shock with a 50,000 hour lifetime. IPX5 waterproof.