The Akrapovič Sound Kit lets the driver adjust the exhaust sound from inside the cockpit. Using the latest technology and working with the car's own electronics, it provides different sound characteristics by controlling the active X-connection built into this Evolution Line (Titanium) system.
For a car with the base Mercedes-AMG exhaust system (no exhaust button in the cabin), the Sound Kit (P-HF949) is a highly recommended upgrade for complete control over the exhaust sound.
If the car already has an exhaust valve button inside the cabin, the sound kit is not needed.
