HEVI-Shot HEVI-Hammer 12 Gauge 1 1/2oz 3 1/2in Shotgun Ammo 4 Shot 25 Rounds. It features 15percent high-density bismuth layered over 85percent steel pellets. The Bismuth layer is the same shot size as the steel. That small but mighty leading edge of bismuth packs nearly 50percent more knockdown power than the steel layer at 40 yards. Specifications for HEVI-Shot HEVI-Hammer 12 Gauge 1 1/2oz 3 1/2 in Shotgun Ammunition: Manufacturer: HEVI-Shot Gauge: 12 Number of Rounds: 25 Shell Length: 3 1/2 in Muzzle Velocity: 1500 ft/s Application: Waterfowl Shotgun Shot Weight: 1 1/2 oz Shot Material: Bismuth Lead Free: Yes Application: Hunting Package Contents: HEVI-Shot HEVI-Hammer 12 Gauge 1.5oz 3.50in Shotgun Ammunition What is HEVI-Shot HEVI-Hammer 12 Gauge 1 1/2oz 3 1/2 in Shotgun Ammunition good for? The manufacturer thinks that it is suitable for waterfowl.HEVI-Shot HS28304: HEVI-Hammer 12 Gauge 1.5oz 3.50in Shotgun Ammo 4 Shot 25 Rounds