This unit is a screw in, catridge type, 2 ported with external third outlet port, 2 positon, hydraulic shuttle valve. Operations: This valve senses the higher of the two input pressures port 1 or port 2 and routes it to the out port. Specifications: Operating Pressure: 5,000 PSI (350 Bar) Flow : 23 LPM Valve Housings: 2,500 PSI (210 Bar) = Aluminum 5,000 PSI (350 Bar) = Steel