This system produced gains of up to +9 HP and +10 lbs. x Ft. TQ., as measured on our in-house dyno. This cat-back exhaust system is constructed of 3 IN to 2-1/2 IN mandrel-bent brushed finished 304 stainless steel tubing for maximum strength and durability. This system features a high-flow high-temperature metallic black muffler, producing a powerful sound. The muffler has a high-temperature metallic black finish for ultimate corrosion resistance. Finishing off this exhaust system are quad 4-1/2 IN diameter carbon fiber stainless steel clamp-on exhaust tips. The tips features an aFe POWER logo for a unique style. This system produces a powerful sound unleashing all available horsepower and torque. Utilizing factory style flanges and hangers this system is a direct bolt-on system, which requires no cutting or modifications for a hassle-free installation. This cat-back exhaust system uses a heavy duty flex pipe with an internal interlock liner for added strength and durability. The aFe Muffler features an integrated x-pipe to balance and evenly distribute exhaust pulses traveling through the exhaust system, minimizing exhaust drone and maximizing scavenging. This axle-back exhaust system incorporates factory style NPP dual mode & AFM (active fuel management) exhaust valves which use the factory exhaust valve motors (not included). The valves helps regulate, direct and control the flow of exhaust gases by opening, closing, or partially obstructing passageways depending on throttle position for maximum performance. Utilizing state-of-the-art computer-aided design technology, this exhaust system is designed for custom, high tolerance factory fitment. 100% TIG-Welded for race-proven strength and durability. This item will only fit vehicles equipped Z51 Performance Package or the factory performance exhaust upgrade that include NPP dual-mode exhaust valve. This item is not recommended for track use.