The Whitman Controls P845 Differential Pressure Switches are rugged and versatile, with excellent by-pass characteristics and the ability to handle a wide variety of media to 6,000 PSIG and set point ranges to 250 PSID. These switches are NEMA 4 rated and can tolerate submersion. They are commonly used across oil and water filter heads to detect when a filter element needs changing. It may be mounted in any orientation and is capable of carrying light to moderate mechanical shock and vibratory loads.