Parts & Accessories Spare parts Product specifications and features: Muffler size is 3 inches. Muffler valve thickness is 4 mm (the highest thickness among usual valve plates). Benefit: stronger resistance to backfire and detonation. Fox muffler system. Made of 304 stainless steel and TIG welding. Sound on/off via remote control. Exhaust tip for faster air exit, increasing the car's power. A noticeable increase in sporty performance and horsepower. Compatible with most cars.