The TLR-2s by Streamlight has the same great features as the TLR-2 plus a strobe function. 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 model features an ambidextrous momentary/steady on-off switch, and a double tap of the momentary paddle within 0.4 seconds activates the strobe. This tactical light has a 650-660nm red laser, and it will run for 48 hours in the laser-only mode. The water-resistant TLR-2s includes rail locating keys for Glock-style, 1913 Picatinny, S&W 99/TSW, and Beretta 90two firearms.