[velosam]

Originally Posted by Darkness

Looks like it bolts to a pair of brackets on the headlamp ears.

https://www.stein-dinse.biz/eliste/index.php

The bottom fiche for the S4 2001 shows this.

Looks like a special bolt but can't see any reason why a standard bolt wouldn't do the job. The other bit fits on the indicator bolt (I think).