I have been single dosing my espresso for a couple of years now and started using these small 4 oz quilted Ball brand mason jars. I was keeping them in a drawer, but wanted something more accessible. This model [single] holds 4 Ball mason jars stacked, and the triple holds 4x3 for 12 total.

I like to have 3 different coffees at a time available for espresso and pour over, so I use stickers on my jars to indicate what roast they are [key on a whiteboard at my coffee station]. This allows me to keep those 3 out at any given time in their own stack.

This is my first 3d model so I'm sure if it's useful to anyone else, you'll be able to refine it a bit more if necessary. Happy to take feedback/suggestions.

The first print/test of the files is printing now and I'll update with pictures after it completes.

Designed in Tinkercad