The Baader steel leveling flange for the 10Micron GM4000 mount, consists of a precision milled top plate (upon which the mount is fitted) connected to the base plate by six steel bars. The base plate is attached to a pier.
The flange allows also an accurate levelling of the mount without reducing the stability of the pillar.
The steel pillar flange #1454090 is required
The photo below shows how the flange is attached to a pier with the connection/levelling bolts with a mount attached.