Specifications: Set Sizes Include: 29mm - 30mm - 31mm - 32mm - 33mm - 34mm - 35mm - 36mm - & 38mm All by 1/2" Drive Each Socket Has A Drilled Head To Locate Retaining Ball Bearing On Most Breaker Bars & Impact Wrenches To Ensure A Safe Secure Fit FOR True IMPACT For Exceptional Strength & Durability Description: .