The system is designed to replace the secondary catalytic converters, providing improved exhaust gas flow and reduced back pressure. This allows the engine to operate more efficiently and gives the exhaust a deeper, sportier tone. All components are made from aerospace-grade 304L stainless steel, ensuring durability and corrosion resistance. An excellent choice for those looking to enhance engine performance and responsiveness. Specifications - Pipe diameter (inches): 4.0 - Resonated: No - Feature 1: To OE Axle Back Only