For use on S&W J-frame 642/442/637/638/438 Revolvers Tough reinforced nylon design offers superior integration with firearm frame Easily programmable for steady or high-vis pulsed beam Ten minute automatic time-out prevents inadvertent battery drain Ambidextrous TAP ON/TAP OFF switch reinforces safe firearm handling Fully adjustable for windage and elevation; Class IIIa Laser Product: &lt;5mW power output Class IIIA laser, &lt;5mW power output