The Archangel 7rd, 12 gauge shell carrier mounts to the side of the receiver on Mossberg 500/590 shotguns. A retention adjustment system allows for the individual tension adjustment for each shell allowing the user to fine tune the shell carrier for specific ammunition and the level of retention required. A rubber molded gasket fits between the mount and the receiver to protect the firearms finish. Shell carrier will not contact or interfere with the pump action forend when used with military length forends. Made in USA.