This Atlas Cat - Back exhaust system is constructed of 4 in. mandrel - bent steel. Comes with Tubing OE Style bayonet hangers band clamps and all hardware necessary for a hassle free installation. The smooth curves and increased diameter of this exhaust system helps remove restriction and keeps exhaust gas flowing smoothly for increased horsepower and torque. Installation is a snap. This system uses all factory mounting locations providing stability and a hassle free installation. High quality OE style flange and band clamps are used for a complete 360 degree sealing surface eliminating leak paths. OE style bayonet hangers are used to maintain a stable pipe location during high vibration and high heat conditions.