Borla 10408 Cat-Back Exhaust System with X-Pipe for Shelby Mustang GT500 428 CID V8 Fits Shelby Mustang GT500 1967 428CID V8 manual transmission models 300 series stainless steel Emmissions legal and Carb approved in all 50 states Two 3 inches round rolled angle cut tips Has 2.5 inch piping diameter