A simple table clamp modeled to hold your guitar for you. Should work for any tables up to 3 cm thick. The jaws open up to 4 cm, but the clamp might slip off.
Getting the right spring and pin might be complicated. I used pin and spring from a table clamp / cup holder (i.e.: https://allegro.cz/nabidka/drzak-na-hrnek-stolu-gimex-tyrkysovy-klip-9919002388)
For printing I recommend higher infill (35-50%) and additional perimeters (3-5) to avoid the model cracking.
The author marked this model as their own original creation.