The TLR-1s by Streamlight is an intensely bright, virtually indestructible strobing tactical light that attaches/detaches to/from almost any gun in seconds. The rail grip clamp system securely attaches/detaches quickly and safely with no tools and without putting your hands in front of the muzzle. This tactical light mounts directly to handguns with Glock-style rails and to all MIL-STD-1913 (Picatinny) rails and includes keys for Glock-style, Picatinny, Beretta 90two, S&W 99, and S&W TSW. The TLR-1s features an ambidextrous momentary/steady on-off switch, and a double tap of the momentary paddle within 0.4 seconds activates the strobe function. It is waterproof to one meter for 30 minutes.