Trinity red laser features: Weaver mount will easily clamp onto handguns that have a weaver style accessory rail under the barrel. Fully adjustable for windage and elevation on/off rear cap switch is easily turned on or off with your trigger finger All aluminum construction 635-655nm Red laser beam <5mw specially designed Weaver style mount standard on/off cap switch Includes 3 ag13 lithium type batteries and mounting tool dimensions (inches): 1.61lx1.04 wx1.19h Weight: 1.2oz. with batteries.