For This is our pro model 1/2" drive air ratchet. Works with 1/2" drive sockets. Just hook it up to an air compressor and you got a right angle power wrench. Specifications: Square drive: 1/2" Capacity bolt size: 1/2" (13mm) Free speed: 160 RPM Max. torque: 50 FT-LB (69 N-M) Air inlet (PT):1/4" Air hose (ID): 3/8" Avg. air consumption: 4 SCFM Working pressure: 90 PSI (6.3 BAR)