Audi RS6 C8 4.0 V8 bi-turbo (Non OPF/GPF Models - USA/ROW Models) YOC: 2020 - 2023 Part: Cat-back Info: Cat Back System Non Resonated (Twin 80mm) with Polished Oval Trims (Loudest) - Requires OE system to be Cut - Designed for Customers who will be upgrading to Turbo Back in the Future tailpipe design: pipe diameter: 80mm /3,15inch EC-approved: No Race system: No Valvesonic: No Part no.: SSXAU864