The Mossberg 590A1 is the military-spec variant of the 590, adding a heavy-walled barrel, parkerized finish, metal trigger guard, and metal safety button. 9-shot capacity. U.S. military contractor-proven. The 590A1 meets or exceeds all MIL-SPEC requirements. Type: Pump Shotgun Action: Pump-Action Caliber: 12 Gauge Capacity: 9 Year introduced: 1990, USA Weight: 7.5 oz Overall length: 41" Status: Active Military use: Yes Intended use: Military, Tactical, Law Enforcement, Home Defense