3D Vector intended for Physics teachers who teach magnetism (and other topics) where it is useful to have a vector that points "into" and "out of" the page. This design includes a place for a 0.5" diameter x 0.25" tall magnet to be press-fit into the top and bottom of the arrow, so that the arrow can stick to a magnetic whiteboard. I use the following magnets: https://www.magcraft.com/magcraft-nsn0641

I also plan to create a similar version of this that works with the magnets that come with the Vernier Carts and tracks. I'll post that version once I've designed and tested it.