For high-pressure oil and gas drilling and safety shutdown markets, Models P4 and P9 have up to 12,500 psi adjustable set point range. Snap-action Belleville spring assembly provides vibration resistance and set-point stability, and choice of 1/4 in. NPT (female), 1/4 or 3/8 in. medium or high-pressure (male or female) autoclave connections are also available. Mechnical pressure switches are Class I, Div. 1 rated, UL approved, and ATEX certified.