This system features a black chrome finish 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. BORLA Cat-Back 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.