AWE Performance Mid Pipe for BMW 340i440i modelsThe AWE Performance Mid Pipe is non - resonated and replaces the factory resonated section with straight - through 3 - inch T304L stainless steel tubing. Perfect fitment, ready to rumble. IMPORTANT NOTES ABOUT THESE PRODUCTSIf you're looking to equip your F3X with the Performance Mid Pipe only, please note that cutting the stock exhaust is necessary.