Armstrong Drive Socket, Standard Length, Measurement System Metric, 1/4 in Drive, Square Drive, 6 Point Socket, 8 mm Socket, 0.878 in Overall Length, 0.465 in Drive End Width, 0.465 in Socket End Width, 0.209 in Bolt Clearance Depth, 0.68 in Opening Depth, Ball Locking, High Alloy Steel, Chrome Plated