2011-14 Shelby GT500 3" H-pipe. Includes 3" lead pipes, clamps and rear O2 extensions. Your choice of connection and emissions control.2007-14 Shelby GT500 3" H-pipe with 3.000" OD outlets to fit Stainless Works Headers and Catbacks. Includes 3" offroad lead pipes, clamps and rear O2 extensions. Fits up to Stainless Works Headers P/N GT115H. Is a direct replacement for leads and X-pipe in P/N's GT145HOR/ GT145HCAT. Fits up to Stainless Works Peformance Connect Catbacks for full 3" dia systems.