The patented TacStar Sidesaddle 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. Note: some field grade shotguns may require a modification to the shotgun"s forend. Shotguns using the TacStar pistol grip forend do not require modification. 12 Gauge only.