Mossberg 590A1, Security Mil-Spec, Pump Action, 12 Gauge, 3 Chamber, 18.5 Heavy Wall Barrel, Parkerized Black Finish, Synthetic Stock with M-Lok Forend, 6Rd, Bead Sight 50766 Since 1919, Mossberg has been the leader in introducing important design breakthroughs to the firearm industry. Many product features pioneered by Mossberg are now the standards by which all modern firearms are judged. It is this basis of unquestionable quality that drives Mossberg to bring reliable, well-built shooting systems to you at an affordable price.