This is a LEGO compatible mount for a 28BYJ-48 stepper motor as commonly used in Arduino and Raspberry Pi projects.
The added hardware required.
2/ M3 bolts 12mm lomh
2/ M3 nuts
8/ 6mm ball bearings
1/ Stepper Motor 28BYJ-48 and associated electronics to control it.
for best result mounting to a large Lego Base Plate is to use a layer of smaller Lego blocks between this mount and the flat plate.