Remington Nitro Steel Duplex 12 Gauge 2x4 3in Shotgun Ammo 1.25oz Steel 1450 FPS 25 Rounds. Blended high velocity magnum steel payload gives dense patterns with the smaller shot size close up while the larger shot hits hard close and maintains energy at longer ranges. Specifications for Remington Nitro Steel Duplex 12 Gauge 2x4 3in Shotgun Ammunition: Manufacturer: Remington Gauge: 12 Number of Rounds: 25 Shot Size: 2/4 Shell Length: 3 in Muzzle Velocity: 1450 ft/s Application: General Shotgun Shot Weight: 1 1/4 oz Shot Material: Steel Primer Style: Centerfire Shotgun Pellet Count: 197 Cartridge Case Material: Plastic Lead Free: No Package Contents: Remington Nitro Steel Duplex 12 Gauge 2x4 3in Shotgun Ammunition What is Remington Nitro Steel Duplex 12 Gauge 2x4 3in Shotgun Ammunition good for? The manufacturer suggests that it is best for general.Remington R20321: Nitro Steel Duplex 12 Gauge 2x4 3in Shotgun Ammo 1.25oz Steel 1450 FPS 25 Rounds