NOT recommended for use on convertibles. This resonator contains an internal H - Pipe for increased performance and improved sound. 3 diameter inlets and outlets. It is designed to dampen the sound of our Cat - Back systems 14742 and 14743. Use ONLY with BORLA systems. It is NOT designed to work with competitors or Original Equipment systems. Fits Vehicles With or WITHOUT Active Valve Exhaust. Built from premium T - 304 stainless steel, superior to T - 400 series knockoffs (such as 409), 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 stands behind every direct fit resonator with a Million - Mile Warranty. Just what you'd expect from the world's most experienced (and most winning) exhaust brand.