As you probably guessed, you have to cut the empty filament spool in half and fix it with this tool.
Printer Brand: Creality
Printer: Ender 4
Rafts: No
Supports: No
Resolution: 0.3mm
Infill: 20%
Filament: theveel PETG Translucent
The author marked this model as their own original creation. Imported from Thingiverse.