The Target Hydrautech Pvt. Ltd. In-Line Adjustable Variable DV-DRV Throttle Check Valve w/ Free Reverse Flow, 1/2′′ NPT is suitable for use with any hydraulic system. The valve is used to control flow and shut off in one direction while allowing unrestricted reverse flow in the opposite direction. Precision control enables you to give the precise amount of flow required by the hydraulic system. Rotate the handle to the desired flow setting.