Throttle Check valves are used where volume flows have to be infinitely controlled in one direction while allowing for free flow in the reverse direction. A typical use is the speed control of cylinder or other actuators. The free flow check allows for meter-in or meter-out actuator control. A fine tread on the adjustable throttle reveals an annular gap or triangular notch. The adjusted throttle cross-section produces a pressure drop which determines the volume flow. The volume flow is zero when the throttle is screwed in (the metal sealing edge seals completely). The in-built check valve allows free flow in the reverse direction. We keep a complete range of throttle check valves of all well renowned brands in our inventory.