The Mossberg 590 Mariner is a corrosion-resistant pump-action shotgun featuring Marinecote metal finish and a synthetic stock designed for marine, coastal, and nautical environments where salt air causes rapid corrosion. Type: Shotgun Action: Pump-Action Caliber: 12 Gauge Capacity: 9 Year introduced: 1989, USA Weight: 64 oz Overall length: 41" Status: production Intended use: marine,home-defense,tactical