The R-K DPR series diaphragm pressure regulator is designed to be more sensitive to pressure changes while protecting piping systems. This pressure reducing valve is designed to provide excellant flow ratios over a wide pressure range. Teflo (Primary) and EPDM (back-up) diaphragms are ideal for DI water or other ultra pure applications. Adjustable screw and lock-nut makes pre-set downstream pressure more precise and accurate. Wide working pressure range (5 to 100 PSIG) Top entry and parallel inlet and outlet ports to facilitate installation and avoid piping problems. This compact pressure reducing valve is designed to keep the stainless steel spring totally isolated from the fluid chamber insuring no metal contact with the fluid.