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	2.75"
Ounces	1 1/4 oz
Shot Size	5
Muzzle Velocity
Rounds Per Box	25
Boxes Per Case	10
Shot Type
Shot Material	Steel, Bismuth
Application	Hunting