Acc. to DIN 3122, ISO 3315, With square coupler, medium-fine toothed, extremely rugged, Return angle 10 degrees, For hand-operated sockets and accessories with square drive as per DIN 3120 - D 20, ISO 1174 with locking pin, GEDORE vanadium steel 31CrV3, chrome-plated, Vanadium steel 31CrV3, chrome-plated