Employing frictionless diaphragm as its only moving part, HV Series instantly reacts to changes in system flow to keep pressure stable and at set point. Applications average around 1 psi, and max working pressure is 15 psig in standard model. Valves are pilot operated, and pilot pressure can be applied with manually adjusted mechanical or electronic pressure regulator. Along with choice of body and diaphragm materials, several port sizes and connection options are available.