The 590A1 is Mossberg's heavy-duty military-spec pump shotgun with a metal trigger guard, metal safety, and 20-inch barrel, the only pump shotgun to pass the US military Mil-Spec 3443E test. Type: Shotgun Action: Pump Caliber: 12 ga Capacity: 8 Year introduced: 1987, USA Weight: 80 oz Overall length: 41" Status: Active Military use: Yes Intended use: Military, Law Enforcement, Home Defense