Borla Cat - Back and Rear Section exhaust systems feature patented straight through and multi - core technology to unleash hidden horsepower. Increased exhaust velocity adds power driving excitement fuel economy and the distinctive Borla Sound of power respected enthusiasts everywhere. Each system is built from premium 300 series austenitic stainless steel superior to T - 400 series knockoffs to give you the absolute best in performance and durability. Ultra smooth mandrel bends ensure maximum flow and power and precision computer controlled CNC manufacturing ensures an accurate fit. Best of all Borla stands behind every system with a Million - Mile Warranty. Just what you would expect from the worlds most experienced and most winning exhaust brad.