Uncle Mike's QD Magazine Cap Swivel
Now you can add sling swivels to your favorite pump or auto without altering your shotgun. Uncle Mike's Magazine Cap Swivel Sets for 12 Gauge Pump and Auto Shotguns have a factory magazine cap with the swivel base already installed.
Just unscrew the factory magazine cap and replace it with the new cap. For the buttstock, a 3/4 inch wood screw swivel base is included, along with two Super Swivels.