The Lee Company's new 375 PRI®/Chek® Valve combines the function of a pressure relief valve in parallel with a check valve into one easy to install insert. The relief valve function features a rugged Tungsten Carbide ball and a 440C seat for durability and long life. The remaining components are constructed entirely of stainless steel. The 375 PRI/Chek Valve is available in a range of relief flow cracking pressures for system pressures up to 5000 psi. Maximum restriction in the free flow direction is only 220 Lohms. Each Lee PRI/Chek Valve is 100% tested and inspected in both flow directions to ensure reliable, consistent performance.