This 3" diameter Cat-Back(tm) system contains Merge X-Pipe for increased performance and improved sound. This system INCLUDES MDS (multi-displacement system) valve simulators which ELIMINATE the MDS valves. This avoids any warning lights on the dash while providing maximum flow at all times. The system delivers the classic S-Type sound with no drone inside the vehicle. Tips NOT included. Use factory valance / tips. BORLA(r) Cat-Back(tm) & Axle-Back 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(r) Sound of Power respected by motoring enthusiasts everywhere. Each system is built from premium T-304 austenitic 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(r) stands behind every system with a Million-Mile Warranty. Just what youâ€d expect from the worldâ€s most experienced (and most winning) exhaust brand.