This 2.75" diameter into dual 2" Cat-Back™ system has been tuned specifically for flow, performance, and sound for the 2.5L 4 cylinder engine in the K5 GT. The system features BORLA®'S Polyphonic Harmonizer Technology that 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 system. The system delivers the sporty S-Type sound without any drone in the cabin. The exhaust exits thru dual 3.5" round black chrome on T-304 stainless steel tips on each muffler assembly. 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. A system is also available with bright chrome on T-304 stainless steel tips. Ultra-smooth mandrel bends ensure maximum flow & power, and precision computer numerical control (CNC) manufacturing ensures an accurate fit. Each Borla® Exhaust System is built from premium T-304 series stainless steel to give you the absolute best in performance and durability. We strive to provide you with the highest quality products and stand behind our systems with a Million-Mile Warranty.System Features:Cat-Back™ System S-Type Sound Level Features Polyphonic Harmonizer technology No-Drone Dual 3.5" Round Black Chrome On T-304 Stainless Steel Tips On Each Muffler Assembly Bolt-On Installation T-304 Stainless SteelMillion-Mile Warranty