Additel ADT 925W [ADT925W-B] Handheld Hydraulic Pressure Test Pump, 1/4 BSP Female, 6.000 psi (400 bar) - Deionized Water.  Water is a hand operated pressure pump designed to generate pressure from 85% vacuum to 6,000 psi (400 bar). With the patented screw press technology, the high pressure can be easily generated, as well as increased and decreased smoothly. With no check valve (non-returning valve), the ADT925W-B avoids the troublesome leakage issues that is usually experienced with most 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 ADT925W-B is an ideal comparison test pump for calibrating pressure measuring instruments such as test gauges, indicators or transducers in the field or laboratory.