This unit is a screw in, catridge type, guided ball (-04) or guided poppet (-08 to -16), hydraulic check valve, for use as a blocking or load holding device for high pressure applicatons. Operations: Valve allows free flow from port 1 to port 2 and blocks flow from port 2 to port 1 or holding a load. Specifications: Operating Pressure: 5,000 PSI (350 Bar) Flow : 9.5LPM to 228 LPM Valve Housings: 2,500 PSI (210 Bar) = Aluminum 5,000 PSI (350 Bar) = Steel