The Hypro VDR50 control unit is a pressure regulator that directly mounts onto the Hypro D813 diaphragm pump. It is capable of handling up to 35 GPM and 725 psi. The VDR50 includes a pressure gauge, one adjustable high-pressure relief valve, one bypass lever, two 1/2" HB outlets with shut-offs and one 1" HB bypass.