"Use this Concentric/Barnes High Pressure Hydraulic Gear Pump on mobile equipment, construction and agricultural equipment, machine tools, material handling and mining equipment, PTO pumps, refuse haulers, compaction and baling equipment. Standard 4-bolt mount. 1.78in. diameter pilot with 1/2in. x 1 1/2in. shaft, 1/8in. square key. Heavy duty cast iron pump turns at 4000 RPM max. in CW or CCW direction. Use as a fluid pump or fluid motor. Similar to Parker D Series, Webster YB Series, Rexroth S12, MTED Series. Flexible coupling or belt pulley drive. 90 efficient. GPM 1, 2, Usage Fluid pump, fluid motor, Rotations Per Minute 4,000, Material Cast iron, Shaft Diameter in. 1/2 x 1 1/2, Max. PSI 3,000. Cubic Inch Size 0.129 Flow at 1800 RPM 1.0 GPM Flow at 3600 RPM 2.0 GPM Maximum PSI Cont. 3000 Maximum PSI Intmt. 4000 O-Ring Port Size, SAE 3/4in.-16"