The A20P Series (2 inch/51 mm dial) Switchgauge model is diaphragm activated, pressure indicating gauge, with a built-in switch. These switches are used for tripping alarms and/or shutdown devices. The gauge pointer acts as a pressure indicator and as one switch pole which completes a circuit when it touches the adjustable limit contact. Contacts have a self-cleaning motion to ensure electrical continuity. These built-to-last instruments are face-sealed from the environment by the unique combination of a polycarbonate case and lens, a polished stainless steel bezel, and o- ring seals. Ranges above 30 psi (207 kPa) are totally sealed from the external environment. Ranges available from 0-7 psi (45 kPa) thru 0-400 psi (2.8 MPa).