HEVI-Hammer has 15% high density bismuth, layered over 85% steel pellets. The Bismuth layer is the same shot size as the steel. That small but mighty leading edge of bismuth packs nearly 50% more knockdown power than the steel layer at 40 yards.
Specifications:

Gauge	12 Gauge
Type
Length	3"
Ounces	1 oz
Shot Size	7
Muzzle Velocity	1350 fps
Rounds Per Box	25
Boxes Per Case	10
Shot Type
Shot Material	Steel, Bismuth
Application	Hunting