This storage is meant for round magnets. At the screw cap the diameter is shown. Tip: if you put the first magnet upside down in the tube, the other magnets will be pushed out a bit.
The print files are for diameters of 10, 12 and 15 mm. There is also a parametric FreeCAD file in which you can change the diameter, the length of the tube and the text on the cap.
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Edit 2025-02-26
Threads tubes 6 and 8 mm refined.
Edit 2025-02-17
Made tubes 6 and 8 mm slightly bigger.
Edit 2025-02-10
Added tubes 6 and 8 mm.
The author marked this model as their own original creation.