I did a quick search but didn't find this.

I have new Balo rotors for my W126. I am about to start the job however before I disassemble everything I noted that none of the holes in the new front rotors are threaded?

I believe the rotor is held to the hub by 5 bolts from the inside - however I would expect that the rotors need to be threaded? Part numbers I have (both front and rear and I may have mixed up the boxes so I will post both

Balo 02078 - 126 423 0012 (115 423 0412)
Balo 02041 - 126 421 0012 (126 420 0005)