This International Standard specifies the essential interface dimensions of a connector and its plug for the transmission of 12 V electrical power within the enclosed operator station of agricultural tractors and machinery. The device is intended to be used as a non-environmentally sealed, convenient source for power auxiliary devices, providing a means for the operator to obtain electrical power without altering the tractor/machine electrical wiring harness. The maximum current capacity of the specified device is 30 A: it is not applicable to any other voltage system (6 V or 24 V).