Cast Downpipes are designed to enhance gas-flow and heat management, increasing efficiency and performance gains. The HJS High-Flow Sports Catalyst is engineered to provide high quality and optimal performance as an aftermarket catalyst. This product reduces the density of OEM catalysts while maintaining emission regulations for daily use. Standard OEM catalysts typically have 500-600 cells, while the high flow catalyst reduces this to 200 cells, resulting in improved gas-flow and performance. Milltek Sport is the sole UK distributor of HJS Tuning Catalysts. - Enhances gas-flow and heat management - HJS High-Flow Sports Catalyst reduces cell count to 200 for improved flow - Maintains emission regulations for daily usage - Milltek Sport is the exclusive UK distributor of HJS Tuning Catalysts Specifications: - Pipe Diameter: 80.00 - Fitting Time: 4.5 to 5 hours (including removing OE system) - Race Product: Yes - EMarked: No Kit comes with: - MSAU757: Heat Wrapped 200CPSI Cat Downpipe with OPF Bypass (LH) - MSAU758: Heat Wrapped 200CPSI Cat Downpipe with OPF Bypass (RH) - MSAU761: Connecting Pipes (To OE System) - MSAU792: Downpipe Fitting Kit for Non OPF Cars Vehicle Compatibility: - 2020 and later Audi RS6 C8 4.0 V8 bi-turbo Performance Edition (Non OPF/GPF Models - USA/ROW Models) - 2019 and later Audi RS7 C8 4.0 V8 bi-turbo (Non OPF/GPF US/ROW Models) - 2020 and later Audi S8 D5 4.0 TFSI V8 Saloon / Sedan - Long Wheel Base (Non OPF/GPF US/ROW Models) - 2020 and later Audi S8 D5 4.0 TFSI V8 Saloon / Sedan - Standard Wheel Base (Non OPF/GPF US/ROW Models)