Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:4690913.

This is a pretty basic holder for various sizes of circuit boards. It has slots for the following sizes:

• 2 x 8 cm
• 3 x 7 cm
• 4 x 6 cm
• 5 x 7 cm
• 7 x 9 cm

There is probably a more optimized way to fit all the different sizes together, but this works well enough :)

These sizes all came in a kit I purchased on Amazon