EPDM Lined Barrel Holder Universal Clamp Collets Barrel With 4 Openings, Iceland Universal Gun Barrel Clamp Wide Applicability: 4 Openings accommodate round tube or barrel ., 550 / ., 625 / ., 750 / ., 825 to ., 920 The Wheeler Engineering Universal Barrel Clamp 672286 was built to be precision extruded from aircraft grade aluminum and bonded with non-marring urethane Soft Lining: equipped with EPDM lining to protect the barrel. Wide Applicability: 4 Openings accommodate round tube or barrel .550″ / .625″ / .750″ / .825″ to .920″ Soft Lining: equipped with EPDM lining to protect the barrel Function: Designed to provide a secure hold on barrels while in a vise Clamp W8A (Wingless Clamp with Rigid Angular Jaws, for Large Molars Equipped with two side guard