ECE approved systems are those that comply with Economic Commission for Europe (according to ECE-R59) rules for motor vehicles, vehicle systems and components. EXCEPT convertible. has Active Valve Exhaust valves. Resonator contains a 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.