This 2.5" diameter dual Cat-Back™ system contains a Merge X-Pipe for increased performance and improved sound. It delivers the classic S-Type sound with no drone inside the vehicle. The system features single 4" round bright chrome on T-304 stainless steel tips on each muffler assembly. A system with black chrome on T-304 stainless steel tips is also available. Optional front muffler / resonator 60561 can be added to replace the Merge X-Pipe for additional sound control. BORLA® Cat-Back™ and Axle-Back exhaust systems feature patented straight-through and multi-core technology designed to unleash hidden horsepower. Increased exhaust velocity adds power, driving excitement, fuel economy, and the distinctive BORLA® Sound of Power respected by motoring enthusiasts everywhere.