Fuel pressure regulator from Malpassi Product Details: 1:1 Linear. Pressure range 1-5 Bar For mounting on Fuelrail. Fits directly on the fuel rail on Volvo (On volvo whiteblock 4-5-6 cyl, it can fit in the intake or cylinder head depends on the model not suitable for all versions) Connection to inlet O-ring connection, is called 394 connection.Dimensions bolt pitch 40-55mm. Diameter O-ring 15mm. Connection to outlet 8mm hose.