The AWE Tuning BMW F22 M235i Exhaust Suite is available as: The axle back F22 M235i Touring Edition Exhaust, featuring 180 Technology. As a package, including the axle back F22 M235i Touring Edition Exhaust (featuring 180 Technology) + the AWE Tuning Performance Mid Pipe. If you already have an AWE Tuning axle back F22 M235i Touring Edition Exhaust and are looking to add the Performance Mid Pipe, drop us a line here. All F22 M235i systems are outfitted with your choice of 90mm or 102mm Chrome Silver or Diamond Black, double walled AWE Tuning tips. The AWE Tuning Touring Edition Exhaust is an axle back system that leverages AWE Tuning’s proprietary sound cancellation solution, 180 Technology™, to produce the perfect exhaust note, drone free. If you’re unfamiliar with 180 Technology, learn more through this brief 180 Technology video. The AWE Tuning Performance Mid Pipe is a key component in obtaining the perfect signature aggressive yet sophisticated note from the exhaust. This non-resonated piece removes the factory resonated section and replaces it with straight through 3” T304 stainless steel tubing. As exhaust gases exit the M235i engine and flow into an AWE Tuning 180 Technology™ equipped resonator, they pass through strategically located ports, and into reflection chambers. Sound waves, carried by these exhaust gasses, bounce off the walls of the reflection chambers. By controlling the size and location of the ports and the chambers, we also control when the sound waves exit the chambers. The specific timing of when the reflected sound waves rejoin the main exhaust flow creates a one-hundred-and-eighty-degree out-of-phase sound wave that cancels out problematic frequencies. More on AWE Tuning 180 Technology in the tab above.