ECE approved systems are those that comply with Economic Commission for Europe (according to ECE-R59) rules for motor vehicles, vehicle systems and components. This system will fit Bullitt models. System has Active Valve Exhaust Valves. Front muffler/ resonator contains an internal H-Pipe for increased performance and improved sound. BORLA® Cat-Back™ & 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® Sound of Power respected by motoring enthusiasts everywhere. This system comes with black chrome on T-304 stainless steel tips. Using BORLA® Stainless Steel Polish p# 21461 is NOT recommended with these black chrome tips. We suggest cleaning the tips with hot water and a microfiber cloth.