Tiny and tops in the field! Each of these tucks neatly between trigger guard and muzzle of any railed handgun, with no overhang! The light clears darkness like a floodlight. The Laser is the world's only subcompact weapon-mountable green laser. For immediate, fail-safe activation at draw, they're all equipped with Enhanced Combat Readiness (ECR) technology. 2 modes (continuous or strobe). Aircraft-grade aluminum construction with Zytel® polymer front / rear covers. Each includes 1 CR2 3V lithium battery, 3 rail sets, 1 rail set pin removal tool, 2 adjustment wrenches and 2 mounting screws. Each 1.9" x 1.3" x 1.5"h., 2.33 oz. with battery. You get optimum visibility, maximum deterrence and total effectiveness.