This model uses a part from the Voron0 mod. https://github.com/VoronDesign/VoronUsers/blob/master/printer_mods/Koios/V0_C920_Tophat_Mount/STLs/V0_C920_Mount.STL
It is designed to use 2x heat insert M3*5*4, same as used for the Vorons—and two Socket head M3x8 bolts.
The author marked this model as their own original creation.