The 590A1 Heavy Body designation refers to the thicker-walled barrel specification on the mil-spec 590A1. The heavier barrel resists bending from the stresses of bayonet use and heat buildup during sustained fire. All mil-spec 590A1s ship with the heavy barrel as standard. Type: Shotgun Action: Pump-Action Caliber: 12 Gauge Capacity: 9 Year introduced: 1987, USA Weight: 128 oz Overall length: 41" Status: Active Military use: Yes Intended use: Military, Law Enforcement, Home Defense