Cla-Val Models 350-02 and 3650-02 Electronic Actuated Pressure Sustaining Control Valves combine precise control of field proven Cla-Val hydraulic pilots and simple, remote valve control. Models 350-02/3650-02 are hydraulically operated, pilot controlled, modulating valves designed to maintain constant upstream pressure within close limits. These valves can be used for pressure sustaining, back pressure or unloading functions in a by-pass system. The valves use a CRL-34 pilot control, consisting of a hydraulic pilot and integral controller, that accepts a remote set-point command input and makes set-point adjustments to the pilot.