Its a little bit difficult to search or to explain in an other language if you dont know the "official wording" so sorry for that. The german word is "Lochrasterabstand" (maybe helpful for other germany using google)
thx 4 the link
The Mini Dock is no solution for my project because I need the LAN and GPIO pins.
For playing around I already have the Expansion Dock
finally thx to all :)