These are modular wrench holders for automotive wrenches. They are sized to fit in the drawers of Harbor Freight roller cabinets. They come in single, double and quad for all your final number needs.
Tolerances are fairly tight but easily filed/sanded if your tolerances are off on your printer.
There is a small groove at the bottom of each slot to allow you to use a contrasting color of filament. Just poke it in from the side. (I used a nice bright green.) This allows you to quickly see if a tool is missing.
These will hold small to large wrenches. (I use it on 6mm and ¼" all the way up to 24mm and 1-1/4in.)
They have a spot in the bottom for a magnet to hold them to the box. I used Neodymium Disc 12 x 3 mm magnets with great success. (https://amzn.to/4kuU9jC affiliate link.)
I printed these in PLA with a 20% infill. I tested them in PETG and they work fine as well.
The author marked this model as their own original creation.