Nordic Components Shotgun Barrel Clamp, Designed for 12 Gauge MXT Extensions, Compatible with Most 12 Gauge Shotguns, Features 10-32 Threaded Hole on Each Side for Mounting Accessories and Rails, Not Compatible with Remington 887 (Requires NCBCL-12-887), Compatible with Mossberg Shotguns and Benelli Nova/SuperNova BCL-12-MB