Simple bi-material rings, made using wood PLA and another coloured filament.
Scale X and Y according to your finger size.
Each part has to be printed on top of the previous one, or glued afterward.
On the full modeln, insert filament change at 1/3rd and 2/3rd of the heigh (at 2 and 4 mm).
Lower layer heigh is better.
The author hasn't provided the model origin yet.