Bluestone Construction, Inc.: Building into a Hillside Radium FPR Adaptor 8AN ORB, 11mm Bore, 32mm Spacing, M5. These anodized billet 6061 aluminum adapter fittings allow an OEM fuel pressure regulator (FPR) or fuel pulse damper (FPD) to be reused in an application other than the OEM fuel rail. All fittings permit the unit to be clocked into the proper position. Fitting Threads: 8AN ORB male FPR Threads: M5x0. 8mm Required: Fuel rail must have a 8AN ORB female threaded port. Application: Nissan RB26DETT Nissan RB25DET Nissan SR20DET Nissan KA24DE Nissan CA18DET Saab 9 2X Aero 2. 5L 1994 2000 Subaru EJ20 GC8 WRX STI 2008 2014 Subaru EJ25 GR WRX 2008 2013 Subaru Forester SH XT Mazda RX 7 13B