The MagnaFlow Aluminized Custom Builder Series 18980 i's weight-optimized and engineered to enhance your diesel truck with the dyno-proven performance and powerful resonant sound that weâ€re famous for. Custom Builder Pipe Kit 18980 features durable corrosion resistant aluminized steel construction and includes 4in. diameter mandrel bent pipes. Each component is produced using advanced CNC precision robotic manufacturing and backed by MagnaFlowâ€s 1-year limited warranty. This emissions-legal downpipe-back kit utilizes a Clamp-On inlet connection and is designed to produce Aggressive exterior and Moderate interior sound levels with a Single Passenger Side Rear exit. Professional installation is recommended due to possible cutting welding and fabrication required.