The MagnaFlow D-Fit Performance Exhaust Muffler Replacement Kit Without Muffler 19491 19491 replaces the restrictive factory muffler of your Truck with fast-flowing mandrel bent 3.5in. tubing, while maintaining the OEM piping and tailpipe. Exhaust Muffler kit 19491 features a direct-fit, easy-to-install design and is produced using CNC precision robotic manufacturing techniques. This exhaust system's durable, corrosion resistant stainless steel construction is backed by MagnaFlow's limited lifetime warranty.