The file 2020_Mnt_Center_Spacer_[option].stl that comes with Filamentalist V3 allows it to be mounted to a 2020 extrusion, but if that extrusion is sitting on a table or the top of a printer, it is so short that the large drive wheels of the Filamentalist will touch the surface.
This replacement part is taller, allowing the Filamentalist to clear the surface underneath the 2020 extrusion.
The author marked this model as their own original creation.