This Borla(r) Cat-Back(tm) system for the Acura Integra and Civic Si is designed specifically for these vehicles. The 2.5" diameter system features Borla(r)'s Polyphonic Harmonizer Technology which utilizes patented units that contain pipes of different diameters and lengths to create multiple exhaust notes that harmonize to deliver a clean, rich, full-bodied sound to the Borla(r) mufflers. The muffler then enhance this sound to the character and volume appropriate for the aggressive ATAK(r) sound level that this system delivers. Borla(r) is so confident of our engineering and technology in this system that we offer a no drone guarantee. System features single 4.5" round black chrome on T-304 stainless steel tips on each tail pipe. Using Borla(r) Stainless Steel Polish p# 21499 is NOT recommended with these black chrome tips. We suggest cleaning the tips with hot water and a microfiber cloth. Systems with bright chrome on T-304 stainless steel tips, and carbon fiber tips are also available. 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 you'd expect from the world's most experienced (and most winning) exhaust brand.