Check the listing for details. 12 Gauge 6 Round Side Shell Holder Carrier Kit For MOSSBERG 500 & 590. Condition: New. Listed at 16.95 USD. All mounting screws are included, no gunsmithing required. Easy installation, requires no alterations to the shotgun in most cases. The 6 round side shell carrier gives you quick access to ammunition. this shell carrier holds up to six 12 gauge shotgun shells and all mounting hardware is incldedThe 12 gauge shotgun shell carrier has a quick detach design and easy to install, improve your efficiency by keeping your shell at your fingertips.Carrier: black polymer Mounting plate: black anodized aluminum length: 7 inch width : 2.4 inch weight:5 oz THE Shotshell Carrier mounts 6 extra rounds on your shotgun in a convenient and accessible location for fast reloading. The tough, weatherproof shell carrier is attached to an aluminum mounting plate that installs directly on the shotgun receiver. All mounting screws are included, no gunsmithing required. Installation is easy, and in most cases requires no alterations to the shotgun.