Okay so basically title says it all I want to install a new headunit to my A3 I have a concert 2 stereo but I also have a sub as standard in the boot. I have read many times this needs some special adapter although I have no clue what. Basically if I go to halfrauds tomorrow what lead adapters etc do I need to get this headunit working in my car.
Headunit: Halfords | Pioneer DEH-4400BT - CD Tuner with iPod/iPhone Control
Please bare in mind I will probs go to halfrauds for all the kit so if possible please make sure it's something they sell.