This is Circuit Werks latest "Resonated" Downpipe for the 2013+ Ford Focus ST. This downpipe features a 3" inch diameter design made from high quality stainless steel with a resonator welded in (inner diameter of 71mm, outer diameter of 74mm). This system deletes the factory catalytic converter which is the most restrictive part of any exhaust to improve exhaust flow, increase horsepower, along with improving the overall sound of your car with a nice aggressive deep tone. Most is a straight pipe, while ours is a Resonated Downpipe, which will be slightly quieter than the Straight Downpipes.
As once the Cat is removed, it will be much louder. This is a direct bolt on system with all necessary hardware and gaskets included.