Armstrong Drive Socket, Standard Length, Measurement System Imperial, 3/8 in Drive, 12 Point Socket, 1 in Socket, 1-3/8 in Overall Length, 1.31 in Drive End Width, 1.31 in Socket End Width, 0.98 in Bolt Clearance Depth, 0.8 in Opening Depth, Ball Locking, High Alloy Steel, Black Oxide