4" Turbo Down Pipe for 2004.5-2007 5.9L Cummins with High Mount style turbo on 2nd Gen style exhaust manifold. The upper flange measures 4.6" diameter to mate with S400 exhaust housing. The lower flange connects to the factory exhaust system v-band flange using the OEM v-band clamp. This down pipe is high-temperature ceramic coated and includes heat wrap with clamps and a 4" V-band Clamp for turbo connection. Also compatible with 2003-2004 model year trucks which have updated their exhaust system front pipe to the 2004.5-2007 style part.