This Vacuum pump can generate negative pressure/vacuum and pressures from 16 to 25 bar (depending on the model). An additional pressure gauge is required for reference measurement of the set pressure of the Vacuum pump (optional). The fine adjustment on the valve allows each calibration pressure to be set accurately and quickly. This Vacuum pump is ideal for testing measuring equipment, e.g. for testing pressure gauges and pressure transmitters. The reference device for accurate actual pressure measurement is screwed directly onto the hand pump.