Sockets held absolutely securely by push-button lock with ball in the square drive, Direction changed by 2 push-buttons, marked R and L, on the shaft, Return angle 10 degrees, Square drive acc. to DIN 3120 - A 12.5, ISO 1174, chrome-vanadium steel 31CrV3, VDE insulation up to 1000 V, acc. to EN 60900/IEC 60900