Active Valve Control (AVC) is available to support both vehicles equipped with factory valves on the exhaust as well as a growing range of upgrades Milltek Sport offers to have performance exhaust systems with Valve Control. Also with optional App control on selected models, via iPhone or Android smartphone apps, AVC brings total control of the exhaust to the drivers finger tips, via full CAN BUS integration with built in safety controls, Millteks AVC enables the driver to choose when the valves open and close to tune the sound and volume of the exhaust.