I have the SK in 3/8 and 1/2 drive, select sizes. My 1/2 ones use roll pin and there is no play between the socket and the hex like some proto hex bit sockets. I have the half inch drives in 3/8, 1/2, 9/16, and 5/8...chrome hand sockets. I also have an Armstrong 3/8 Dr impact set that I drive w...