For the magnet version, I use 2x N52 Neodym Magnet size 2mmx6mm.

After printing, just add 2 magnets to the holes and glue both halves together.
There are 2 other versions, which are “just” multicolor, but without magnets.
One has a ring, but besides that is the same.

They are AMS ready, oriented correctly and color is assigned, but you can change it of course at any time.