Profi Kits: The 2DIN panel comes with a SteeringWheel Remote Control Interface (which also controls the original display if possible), if needed antenna adapter and other connecton cables, replacement loudspeaker (for parking distance control, safety belt alert,...). So you don’t need to order any additional parts. The reason why everything is in one package is because for these cars, you need this kind of parts in order to let everything work in the car. Just installing the 2DIN panel would make no sense.