The Remington 870 Marine Magnum is fully electroless nickel plated inside and out — action, barrel, receiver, and all internal parts — making it the most corrosion-resistant pump shotgun built for maritime and saltwater environments. Type: Shotgun Action: Pump-Action Caliber: 12 Gauge Capacity: 6 Year introduced: 1992, USA Weight: 240 oz Overall length: 38.5" Status: Active Intended use: Maritime, Home Defense, Coastal