1/4" hex shank to 1/4" socket---- 1/4 " shank can be converted to 1/4" (6.35mm) square head. 1/4" hex shank to 3/8" socket----- 1/4 " shank can be converted to 3/8" (9.53mm) square head. 1/4" hex shank to 1/2" socket ----1/4 " shank can be converted to 1/2" (12.7mm) square head.
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