20mm Barrel Rail Mount Tube Adapter, Rifle Gun Laser Flashlight Barrel Clamp, Scope Mount with Barrel Adapter Easily to attach tactical laser sight or flashlight. Fits both Picatinny/Weaver accessories and mounts. Wide clamping range. fits tube from 10mm-20mm diameter Installs easily and wrench is included Right to your barrel,Great for mounting flashlight, laser sight, bipod,etc.