This fuel rail features 3 large threaded ports (ends and one on the bottom) that are -8AN ORB female. It also has a 1/8NPT female port on the top. Appropriate fittings must be selected based on the specific application. Ample space around the fuel rail port(s) is necessary for larger accessories such as fuel pressure regulators, fuel pressure gauges, and fuel pulse dampers. This fuel rail features an extra 8AN ORB port in the center on the bottom. This can be used as a location for a Radium FPD-R fuel pulse damper (P/N 20-0176). This fuel rail kit is designed for the Nissan S13 SR20DET (RWD configuration) intake manifold. Radium Engineering has NOT tested on any FWD SR20 intake manifolds. This S13 SR20DET fuel rail will also work on most aftermarket intake manifolds that use the OEM fuel rail.