Print settings:
Ideally should have ≥ 3 inches of clearance between the wall and front of the vanity and the surface it's adhering to should be magnetic.
Magnet size is:
Complements the following toothbrush holder - https://www.printables.com/model/224973-hexagon-toothbrush-holder-magnetic-under-vanity
The author hasn't provided the model origin yet.