This cat-back exhaust system is constructed with 3" - 2-1/2" mandrel bent brushed finished 304 stainless steel tubing for maximum strength and durability. Black Stainless Steel Muffler: This system features a black stainless steel muffler, producing a deep sound. The muffler has a black finish for ultimate corrosion resistance. Muffler Bypass Tubes : Dual Muffler Bypass Tubes are integrated into the system to optimize sound tuning. Quad 4 inch Diameter Polished Exhaust Tips IN : This exhaust system is completed with 4 inch diameter polished 304 stainless steel exhaust tips. End caps feature a laser etched aFe POWER logo for unique style. Deep sound : This system produces a deep sound releasing all the power and torque available. Installation: Using factory-style hangers, this system is a direct bolt-on system, requiring no cutting or modification for hassle-free installation. Exhaust Valves: This cat-back exhaust system incorporates factory-style exhaust valves that utilize the factory exhaust valve motors (not included). The valves help regulate, direct and control the flow of exhaust gases by opening, closing or partially obstructing the passages depending on the position of the throttle for maximum performance. Computer-Aided Design: Using state-of-the-art computer-aided design technology, this exhaust system is designed for custom, high-tolerance factory fitment. TIG-Welded : 100% TIG-Welded for race-proven strength and durability.