This model is a Ukulele holder that can be clamped to a desk using the modular clamp by BKoch00, it requires supports and it is recommended to print it in a material with low creep, my version made with abs holds up fine for a few months now

The link to the clamp is: https://makerworld.com/en/models/161469-simple-modular-clamp-with-hook-for-headphones#profileId-177249