The MPB-TAC is one of the most versatile tactical shotgun sights available today. The sight body is an overmolded steel spring that clamps down securely to most 12 gauge shotgun barrels. It is easily installed and easily removed with no tools required because the sight self-centers behind the front bead for perfect alignment. It can fit on shotgun models with extended magazines as unique cutouts ensure the sight does not interfere with the magazine clamp. The interchangeable LitePipe is enclosed to provide protection against breakage without obstructing the target. Fits most 12 gauge plain barrel shotguns without ventilated ribs. Fiber Diameter: 0.135″.