This quality RAGE performance big bore exhaust system will not only increase the power output of your engine, but will also sound good too! Complete with stainless steel rear muffler this system is a simple bolt on solution, designed specifically for 2001 on Subaru WRX! The kit is comprised of 4 components (Front pipe with cone, high flow cat unit, intermediate muffler and rear muffler) which measure 76mm in diameter. The 4 components can also be purcahsed separately if required. Part number BB9001 (complete kit).