Winchester's Premium Bismuth Shot is tin plated, smooth and rounded. Buffered payload puts more pellets on target for 60 yard performance, while water resistant-lacquered primer and double seal was keep out water.
Specifications:

Gauge	12 Gauge
Type
Length	3"
Ounces	1 3/8 oz
Shot Size	4
Muzzle Velocity	1450 fps
Rounds Per Box	25
Boxes Per Case	10
Shot Type	Buffered
Shot Material	Tin-Plated Bismuth
Application	Hunting