Catless high flow design , featuring cat like appearance to give an OEM appearance. Constructed from 304 High-Strength Stainless Steel and equipped with stainless steel and Replacement of the stock downpipes will improve performance, reduce back pressure, increase turbo spooling and increase sound output. Laser cut flanges perfectly match the stock Audi 4.0 litre exhaust system and include all necessary mounting hardware and clamps.