Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:3954128.

At my work we use dry erase markers to write stuff on a board. I didn't like any of the other designs on here because they all kept the tip pointing up. This causes the fluid inside to move away from the tip and make it "dry out". I designed this one so the tip stays pointed down and keeps the ink there.

On the back is spots for 5mm x 5mm x 3mm thick magnets. You can use as many or as little amount of magnets as needed.

I have also included the Fusion 360 file if anyone wants to modify it.