Pressure Switch with built in relay - 165 PSI On to 200 PSI Off For 12-Volt systems only up to 40 amps. Moisture resistant and tested to last over 10,000 cycles. Leads are pre-fitted with insulated male push-to-connect terminals that are clearly marked. Measures 4.25"L x 2.25"W x 2.25"H Tolerance is +/- 5% of specified pressures. Included Parts: - 1/8" (M) NPT Port Fitting.