The Mossberg 590A1 XS Sight Systems variant is a collaboration with XS Sights featuring the company's premium ghost-ring rear sight and tritium front sight for improved low-light targeting while retaining all standard 590A1 heavy-duty military specifications. Type: Shotgun Action: Pump-Action Caliber: 12 Gauge Capacity: 8 Year introduced: 2010, USA Weight: 8 oz Overall length: 39.5" Status: Active Military use: Yes Intended use: Military/Tactical