The unique Quick Detachable (QD) design stops the metal swivel body from contacting the gun. The close machining tolerances provide smooth and silent operation. Super Swivels do not include studs. All others include studs or barrel bands, depending on type. NoteMounts on most pumps and autos. Does not mount on Browning 2000, Winchester 1400, Ithaca 37, Savage 30, Sears 21, 30 or Stevens pumps without Cap modification FeaturesDesign stops the metal swivel body from contacting the gunClose machining tolerances provide smooth and silent operationDoes not include studsFits most pump/auto shotguns but certain models require modification