JTS Group M12AR-B1, Semi-automatic, AR, 12 Gauge 3, 18.7 Barrel, Cylinder Choke, Black Color, Polymer Grip and Fixed Stock, 5Rd, 2 Magazines M12AR-B1 Whether you shoot recreationally or are on a mission to defend your home front, JTS shotguns are built with power, versatility and purpose in mind. Based upon the semi-automatic AR pattern, the MK12AR-B1 shotgun features a 4-position adjustable gas system for use with different loads. It comes equipped with a chrome lined barrel threaded for use with Rem Choke tubes, polymer forend, a fixed AR-style buttstock and comes with (2x) 5-round box magazines.