This choke uses a special field-tested constriction and length to get the most from Blind Side Ammunition's new configuration. Carlson's Blind Side Choke Tubes allow Winchester Blind Side HEX Steel Shot and Diamond Cut Wad to do its job and helps deliver devastating downrange patterns.This choke tube performs equally well when used with other steel shot loads. Carlson's Blind Side Choke Tube is a proven performer on waterfowl using all steel shot loads over extended distances.This choke is also designed to shoot lead plated copper and nickel shot as well as all Hevi-Shot ammunition with great results.