a whole or half model of a D20 Dice to hang onto e.g. your fridge with a 5 x 3/2/1mm round magnet. 20 is on top.

choose the fitting one from the files below

I print mine with a Bambulab P1S and these settings:

Layer height 0.2mm
Wall thickness 1.6mm
Wall line count 2
Top/Bottom Thickness 1mm
Infill density: 15%
Infill pattern: Gyroid
Support: tree - normal