The 20P 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 shut-down 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. The gauge mechanism is enclosed in a steel case coated to resist corrosion. A polycarbonate, break resistant lens and a polished, stainless steel bezel help protect this rugged, built-to-last instrument. Ranges available from 0-7 psi (45 kPa) thru 0-400 psi (2.8 MPa).