Summary

I needed a tray to hold pens, and I wanted it to stick to the whiteboard using magnets. Since I could not find one that I liked, I created this and thought it was a good chance to try out Customizer.

There are three slots for magnets, but I found out that two strong neodymium magnets (18 mm diameter / 2 mm thick) hold the tray well enough for my purposes. You can get those magnets here.