Our oil pressure switches are rated for 100 psi operating pressure but can take momentary over-pressures of up to 500 psi. If your engine regularly exceeds 100 psi, the switch should be replaced each season for highest reliability. The pressure and temperature switches are easy to install and connect to either of our warning lights. All switches are single terminial grounding types. For highest reliability, we recommend that all pressure switches (and senders for electric oil pressure gauges) should be isolated from engine heat and vibration by using our Combination 4AN Bulkhead Mount and 1/8 NPT Adapter, Part No. 3208-02-04S (sold separately).