[urq] I have both styles of caliper carrier bolts - but I think the self-locking is preferred.

[steven j]

ETKA update 525 shows both types for cars >D 581 on Illustration  6_15_54-10 



6      N 012 042 4      lock ring              12 4
7      N 010 137 1      screw, hex. hd.    M12X1,5X35 4

or 
7A    N 907 085 02   self-locking screw M12X1,5X35 4

I have the G60's anyway.  Based on some comment in the Bently manual I think Audi standardized on the self-locking.  I need to order a few more.