Install the Bailey Hydraulics Chief 4-Bolt Flange Hydraulic Pump. It's a compact, 2-stage, external gear pump designed for use at elevated pressures. Ideal for press-type applications requiring fast approach/retract speeds and slower peak actuator work speeds due to horsepower limitations or safety constraints. It's clockwise viewed from the shaft end. 1/2 in. shafts use 404 wood ruff key. 5/8 in. shafts use 3/16 in. 3,600 RPM max. Maximum pressure 3,045 PSI.