Requires at least 1 3/4" of rail space Complete constant beam red laser kit for your black rifle Constant beam red laser with momentary switch and switch control system Built-in accessory rail to mount tactical lights or other accessories MantaRail switch control system securely fastens momentary switch and eliminates the need for velcro or other adhesives MantaClips keep the cord close to the rail to prevent snags and hangups; Class IIIa Laser Product: &lt;5mW power output Class IIIA laser, &lt;5mW power output