For the steering wheel controls you will have to connect one cable manually. No need to buy any adapter or kits for this. There is a pink cable in your car that need to manually connect to a cable called W+ in the unit. This is not plug and play. No need to cut the cable but your installer will do a manual connection to this cable. After that you will have to program the buttons that will be a simple step to follow in the unit configuration section. Also please note Bluetooth phone answer button on your steering wheel controls (if you have) will not work with this unit. Other buttons such as Vol+/- Channel Change, Source buttons will work.
For more details about H520, please visit AutoGPS.com.au
You will need to cut the pink and black wires on existing wiring loom and then join the pink wire to SW 1 cable and Black wire to SW 2 cable.
After installation, follow the steering wheel programming instruction on the manual.