Powered by two 3-volt CR123 lithium batteries with 10-year storage lifeC4 LED technology, impervious to shock with a 50,000 hour lifetime (TLR-1: 300 lumens, TLR-1s: 300 lumens)Deep-dish parabolic reflector produces a concentrated beam with optimum peripheral illuminationStrobe function with user programmable strobe enable/disable (TLR-1s only)Run Time: 2.5 hours regulated run time. Solid-state current regulation for consistent illumination level.Rail grip clamp system securely attaches/detaches quickly and safely with no tools and without putting your hands in front of muzzleMounts directly to handguns with Glock-style rails and to all MIL-STD-1913 (Picatinny) rails.Includes keys for Glock-style, Picatinny, Beretta 90two, S&W; 99 and S&W; TSWMachined aluminum sealed construction with black anodized finishWaterproof to one meter for one hour, dustproofAmbidextrous momentary/steady on/off switchDouble tap of momentary paddle within 0.4 seconds activates strobe. (TLR-1s only)Highly accurate sight repeatability when remountingFits existing light bearing holstersWeight: 4.18 oz.Lithium Battery Notice under TECH DOCSIPX7 rated design; waterproof to 1 meter for 30 minutes.MIL-SPEC 810F Performance TestedStreamlight TLR-Series fits most handguns with rails as well as long guns with 1913 (Picatinny style) rails