The 937 Hydraulic High Pressure Calibration Pump is a hand operated pressure pump designed for calibrating pressure measuring instruments with phosphoric acid ester fluid and Skydrol oil in the range from 85% vacuum to 15,000 psi. With the patented screw press technology, high pressures can be easily generated, increased and decreased smoothly. A specially designed shut-off valve makes the pressure as stable as possible during calibration. With no check valve (non-returning valve), the 937 avoids the troublesome leakage issues that is usually experienced with hand pumps and allows for minimal maintenance. Two hand-tight quick connectors installed on the pump allow easy connecting and disconnecting to the test pump without the need for PTFE tape or wrenches. The 937 is an ideal comparison test pump for calibrating pressure measuring instruments such as test gauges, indicators or transducers in the laboratory.