Invidia G200 Turbo Back Exhaust w/Hyperflow Down PipeHyperflow Exhaust Down Pipe The Hyperflow Exhaust Down Pipe with a high flow catalytic converter uses a massive cast 304 Stainless Steel Bellmouth that tapers to 3. 0 inch piping where it connects to the mid pipe. Unlike previous designs, the new downpipe will bolt to any stock or 3 inch aftermarket catback exhaust system. Bolt On for Forester XT models which commonly have clearance issues with other down pipes. Features: Two piece design: Reduced