Three simple filament clips. The filament threads through the eyes and the face tucks between the spool and filament. Print some for fun or to rank your filament: Amazing! Like it! Sucks! The more flexible the material the better. I printed mine with standard PLA and it works fine. Stiffer materials won't flex enough without breaking.
The eye holes are 5mm. Diameter of clip is 30mm. Thickness is 0.8mm, but that can be easily changed by changing the Z scale. Still work well down to 0.5mm, but you'll need at least two layers of material. When printing at 0.5mm, the clip can be pushed through/into the spooled filament.
The author hasn't provided the model origin yet.