The Prince valve model RV is a differential poppet type inlet relief. The valve is made up a relief cartridge and a cast iron valve body. The differential poppet type relief provides smooth quiet performance with a minimum variation between cracking and full flow pressures. This type relief is also less sensitive to system contamination. The model RV is well suited as a system relief up to 30 GPM and 3000 PSI. It is available in two pressure ranges and both an adjustable and shim adjustable version.