The Pressure Hand Pump is a compact, lightweight, portable hand-operated pressure and vacuum pump. When a digital calibrator is added the unit can be used to calibrate or check pressure measuring devices in the field. No external power or high pressure bottles are required. The pressure pump is completely assembledand ready to connect to the pressure device to be calibrated. Calibration is quick and simple since the pump is taken directly to the pressure device. This pressure pump provides a source of air pressure, 0-600 psi, or vacuum,0-28" Hg.