Use this exhaust when you're cruising on the highway or tearing up the track. It's perfect for BMW enthusiasts who want better performance without sacrificing daily drivability. The exhaust has a dual 3" T304L stainless steel downpipe - back configuration. It comes with a stamped stainless steel merge upstream, and the exhaust splits into dual 3" piping for optimal flow. Whether you have a stock or aftermarket downpipe, there's an option for you with easy conversion available.