The Akrapovi? Sound Kit allows the driver to easily adjust the sound of the exhaust from inside the car’s cockpit. Using the latest innovative technology and working with the car’s own electronics, the Akrapovi? Sound Kit provides different sound characteristics through the control of the active X-connection built into this superb Evolution Line (Titanium) system.If the car is already equipped with exhaust valve button inside the cabin, sound kit is not needed.Pictures are symbolic.