Mercedes AMG E53 (C238 Coupe) - Catback Exhaust (CES3**uses OEM Tips** The iconic CAPRISTO Valved Exhaust System offers the best of both worlds through its capability to produce an aggressive exhaust note under acceleration, and a more subdued sound for city driving. This feature is possible using vacuum actuated valve flaps that open and close depending on driving conditions and input from the driver. At lower engine speeds and during cruise operation the valves are closed and produce a deeper exhaust