This Cat-Back system is specifically tuned for performance and sound on the GR Supra’s 3.0L twin-scroll turbocharged inline six engine. The system is 3.5" diameter that splits into dual 3". It includes 1) 3.5" O.D. x 3.18" I.D. x 4.75" long adapter for clamp on installation to the stock exhaust system. Do not use the adapter for a full 3.5” inlet. Our system is designed to be drone-free so you can get the head-turning ATAK sound and enjoyable tone inside the vehicle. The system includes our 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 mufflers. The mufflers then enhance this sound to the character and volume appropriate for this aggressive ATAK system. The system also has a functioning valve that works with the factory actuator to change the exhaust volume. This system comes with single 4.5" round black chrome on T-304 stainless steel tips on each tail pipe to complete the look of the exhaust. Using BORLA 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 & 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. Ultra-smooth mandrel bends ensure maximum flow & power, and precision computer numerical control (CNC) manufacturing ensures an accurate fit. As with all BORLA products, it is constructed using T-304 stainless steel for increased durability. This is backed by our Million Mile Warranty. Bolt-on a BORLA and give your Supra the power and sound it deserves.