This is an empty shell based on standard trays used by watchmakers. The original trays are made by John Renfer Ltd and are available from a number of suppliers (this is a link to the page at Cousins UK https://www.cousinsuk.com/product/trays-watch-disassembly-assembly-swiss). The clear tops and locking keys allow you to stack and lock multiple trays together. Keys are available to lock between 1 lid and 1 tray, all the way up to 1 lid and 5 trays.

The photos are examples of custom layouts I have created for my own projects. While the tray model is printable as is, it is really a blank canvas for your own custom tray layout.

Due to the nature of 3d printed parts, very small components might be able to migrate from one compartment to another, or out of the tray, if you are aggressive at shaking the trays.

Fusion360 file and step file included to make customisation and modification easier.