This X-Pipe with Mid-Pipes has been developed specifically for the Mustang GT. It is used to connect to Borla(r) Axle-Back systems creating a full Cat-Back(tm) system with a 2.5" pipe diameter to increase power and performance. This part is only to be used with Borla(r) Axle-Back systems. It CANNOT be used with other aftermarket parts or Original Equipment and factory rear mufflers. Fits vehicles With or WITHOUT Active Valve Performance Exhaust. Each Borla(r) Exhaust System is built from premium T-304 austenitic stainless steel to give you the absolute best in performance and durability. Ultra-smooth mandrel bends ensure maximum flow & power and precision computer numerical control (CNC) manufacturing ensures an accurate fit. Best of all Borla(r) stands behind every X-Pipe with Mid-Pipes assembly with a Million-Mile Warranty. Just what you'd expect from the worlds most experienced (and most winning) exhaust brand.