Each set includes two rack holders and a rack. There are mounting holes on each side of the rack to fit onto the holders (they should fit in nice and snuggly).
The hooks on the holder fits onto one specific set of column on the pegboard.
To save on material, you can also print the display rack in reduced Z-height which will work just as fine, albeit maybe with small compromise in holding weight.
The author marked this model as their own original creation.