MagnaFlow XL Mufflers use a unique combination of large diameter perforated tubing and strategically placed sound baffles to reduce unwanted resonance and help your engine create horsepower. The sound baffles tune the sound waves using calibrated tuning gate openings that allow portions of the waves to pass through. These tuned waves reflect off the back wall of the muffler and cancel out unwanted harsher sounds. The large diameter perforated core eliminates the flow restrictions of a louvered style core. A careful balance between perforation size/spacing and the baffle tuning gate make for a great 3 chamber performance muffler. * Stainless steel construction * Multi-chamber design for increased performance * Chambered muffler performance sound