Has a negative space to place 15mmx3mm magnets into the trays. 3MF file will pause at the height to add magnets (I assume this anyway. I had the pause set when I exported the 3MF).

Has letters and numbers in the trays for keeping track of things. I was inspired by a play house that had 7-8 bags of screws that were different. With this you can empty all the plastic bags into the corresponding trays to keep track of them.