This is the last piece of the puzzle to every high flowing exhaust system on your 6.0L. The factory up-pipes on the 6.0L Powerstrokes are extremely restrictive and have poorly designed bends that cause bottlenecks in your exhaust. Replacing your stock up-pipes should be your first step in building a high-performance exhaust system. The PPE Up-Pipe bellows are high flowing, internally sleeved and aircraft grade.