Standard clamp fits most shotguns when used with a Nordic Components Extension. Our tube has an OD of 1.06. - The Nordic Components shotgun barrel clamp provides extra rigidity for your magazine extension. - Fits most shotguns when used with a Nordic Components Extension - Features 10-32 threaded hole for mounting Picatinny rails or other accessories - Not compatible with original Browning Auto-5 or similar shotguns with reciprocating barrel
Determined at checkout.