Armstrong Drive Socket, Standard Length, Measurement System Metric, 3/8 in Drive, Square Drive, 12 Point Socket, 17 mm Socket, 1.012 in Overall Length, 0.925 in Drive End Width, 0.925 in Socket End Width, 0.677 in Bolt Clearance Depth, 0.563 in Opening Depth, Ball Locking, High Alloy Steel, Full Polished Chrome Plated