hI yer all
Allan key to remove the poxy bolt Audi puts in to hold the battery in
Step 1 find a decent tool factor when you enter the shop they should have brands like Facom, Britool, Wera, Gedore, Matarbo, Beta tools and Bosch but the blue range (professional range) you can get the green range anywhere (home uses)
Step 2 ask the person behind the counter if they do Gedore if they do ask them for to order product No.42T gedore code 6353910 I brought one of these makes the job easy it is 6mm T handle allen key 270mm long but Gedore is not the cheapest brand out there it a tool that is guaranteed for life and cost around £11 but you pay for what you get
Failing that and getting the run around from a draper tool factor as they are trying to source one off ebay, I'am sure other tool manufactures do this but I couldn't find any out there over 200mm long apart from Gedore and before any ones moans at me you buy a top quality tool once in your life and I've lent this tool to my mate at Halfords in Bridgwater when he needs to do audi A4
Gedore UK
Marton Street
Skipton
BD23 1TF
Tel: 01756 706700
hope this helps