The performance matches the famous BORLA� systems of the past but with a unique muffler and exhaust configuration canceling additional high frequency sound waves delivering a significant increase in CFM from the factory system which, as most engine builders will confirm, accounts for the dramatic power improvements. Perhaps more importantly, this added flow maximizes performance for other aftermarket enhancements installed on the Mustang because all BORLA� exhaust products are tuned for maximum output from any aftermarket performance upgrade. BORLA�, the original pioneers of aerospace-grade austenitic stainless steel (superior to 409 or aluminized steel) free-flow exhaust utilizes patented award and race winning technology to deliver quality, sound, performance gains and enhanced fuel economy � all with an easy bolt-on installation. Unsurpassed written Million-Mile Warranty