Steelman 7 Piece 3/8 in. For easy identification, each socket has easy-to-read size markings permanently stamped into the steel that won’t wear or fade away. To keep them securely attached to ratchets, extension bars, and adapters, each socket features a ball detent recess on the drive end, and to ensure maximum torque transfer, the drive ends also have corner recesses that transmit applied force to the flats instead of focusing on the corners which can lead to slippage, rounding, and premature tool failure.