I just purchased wheel spacers for my A4 B6 Quattro USP in the sizes of 10mm for the front and 15mm for the back. I have a serious question that the supplier could not even answer except for "I don't know, I think they come like that".

My question is, are the overall diameters of the wheel spacers the same for the front and the back?

As illustrated in the attached pics, they are different diameters. The inside hub of each rim is the same as is the contact points on the disc brakes. I'm afraid that if I install them respectively, that they will either be sticking out and be visible, or have a gap between the rim and the disc brakes. Ultimately the best case scenario would be that they would be flush to the rim and disc brake. I can see a potential danger if the spacer is too small causing vibration or even damaging the rim and/or disc brake. Am I missing something here or did they send me the wrong part? Once I install the spacers, they are non-returnable, which is why I'm seeking advice from all of you Audi experts.

PLEASE HELP!!

The photo's are the two spacers stacked side by side with each other.

spacers1
spacers2
spacers3
spacers4
spacers5

 

Im no expert in wheels spacers (I refuse to use them) but since our discs are smaller in the rear, could it be normal your front spacers are bigger then the rear?

Edit: Just noticed you put them up for sale, IMO just get some 8.5ET32 you will be happy with the stance