Hybrid Racing Black EFI quick disconnect rail fitting 06-11 Civic SiIf you have an 06 11 Civic Si, this piece is for you. Mounted on the end of the fuel rail, this piece mates with the stock fuel line. It features an extended fitting to relax tension on the fuel line and help with clearance. Comes with an O ring to prevent leaks. This fitting is included with the Hybrid Racing fuel line kit if you purchase it for the 06 11 Honda Civic Si. Fits: 06 11 Civic w factory K Series engine (FA5, FD2, FG2 & FN2)