Attachable magnetic screw trays.
While disassembly you sometimes have different screws. To stor and sort them this trys cann be used. On the bottem they have space for a 15x3mm magnet.
There are 9 different trays so you can print them to your belongings 2x2 4x4 6x2 . . . whatever you need. With the given print profile the fit tightly together printed on my P1S.