HAND PUMP The 912 Pneumatic Pressure Test Pump is a hand operated pressure pump designed to generate pressure from 95% vacuum to 60psi (4bar). A high-quality screw press is designed for fine pressure adjustment, with an adjustment resolution up to 0.1 Pa (0.001 mbar). The 912 is a very stable low pressure calibrator. It makes use of an isothermal bellows chamber which is designed for reducing the possible effects of environmental temperature change. Most pumps make use of a check valve (non-returning valve) and are not well insulated which will cause large fluctuations in pressure with a change in ambient temperature or when the unit is touched. The 912 does not use a check valve and is remarkably stable. Two hand-tight connectors installed on the pump allow easy connecting and disconnecting to the test pump without the need for PTFE tape or wrenches. The 912 is an ideal comparison test pump for low pressure applicatio. Features: Portable: Only 6.2 lb Adjustment Resolution:  0.1Pa (0.001 mbar) High-quality screw press for fine pressure adjustment Great Stability: Isothermal chamber: the pressure chamber is insulated to reduce the influence from environmental temperature changes.  Specially designed bellows minimize leakage to guarantee excellent stability. Shut-off valve closes the air in the isothermal chamber during calibration Durable and Minimal Maintenance: Built-in gas-liquid isolator protects the pump from moisture and dirt Easy-to-use Hand-tight Quick Connectors: Allows easy connecting and disconnecting to the test pump without the need for PTFE tape or wrenches Includes: Additel ADT912-B Low Pneumatic Pressure Test Pump, 1/4 Inch BSP Female O-ring Manual