Mossberg 590 Shockwave, 20Ga 3, 14 Barrel, Black Finish, 5Rd, 26.5 Overall Length, Bead Sight 50657 With credentials hard-earned over decades of military and law enforcement use, the 590 Firearm is the perfect choice for your personal and home defense needs. Dual extractors, positive steel-to-steel lockup, twin action bars, and an anti-jam elevator ensure smooth operation.