The author remixed this model.
Combined “Kallax Filament Spool Knob flatter” kallax knob with “Prusa Cabinet/Drawer Pull Knob with smoother filament” side as I liked the prusament spool look better than just a solid circle when viewed from the front.
I just sliced the side from the “Prusament” knob and combined it with the screwable middle tube part from the kallax knob.
Like the “Kallax Filament Spool Knob flatter” this is scaled to 99% from the original “kallax filament spool knob” to make screwing the parts together easier.
Should work with either the original “kallax filament spool knob” or the “flatter” version, depending on your preferences.