Genuine removable towbar part

[thefreak]

Guys,

When I bought my 02 A4 Avant I was told it came with a towbar. When I investigated, it's got most of the parts there. The electrics, the mount behind the bumper, the bracket in the spare wheel well but no ball part (the part you actually attach the trailer to)
I've tried a couple of breakers and they just give a straight NO without even really understanding what I need.
Can anyone else help me source the part... or even just lend me theirs for a weekend :)

I've attached a pic of the bit missing from its place in the spare wheel holder:

http://img.photobucket.com/albums/v65/thefreak/IMG_0066.jpg

[abbey]

Looking at the piece above the swan neck holder, this looks like a bolt on towbar bracket, to make this work, pop to your local halfords and buy the 50mm ball and 2 mounting bolts.

[thefreak]

Hmmm... interesting...
So is the part above an original part too or is it just a generic removable towbar?

[abbey]

Both are available. the largest space is the removable one there is a fixed bracket also, which looks like the bits you have, excluding the 50mm towball.