"12.5 mm (1/2") square drive" Speed at no load: 7000 rpm Max. torque: 230 feet (312 Nm) With 10 pieces of sockets (9, 10, 11, 13, 14, 17, 19, 22, 24, 27mm), the weight is 4.2KG. With connectors of the USA, Italy, Nitto, and Europe types. Air Consumption: 5.0cfm or 142.5l/min Air pressure: 90 psi (6.3 bar) Length: 187 mm, or 7.3 in. Weight: 9.3 pounds (4 kg) Air Inlet: 1/4" 3/8" air hose, packaged by BMC.