Compact spices rack for hanging Bormioli Rocco (popular italian brand of glassware) 4 cl and 8 cl jars.
The jars are held suspended by the collar, the fit is reasonably tight, but there is an additional 5 degrees slant to prevent them from sliding even should the "rails" wear off a little over time.
I do recommend printing multiple shelves as in the photo, so that the top of each one can assure some emergency support to the jars above, just in case.
Warning, the 25 ml jars use the same caps and have in theory the same collar diameter, but they cannot be used because the jar itself "bulges" a little bit more, so they would bump into each other and the wall.
The author marked this model as their own original creation. Imported from Thingiverse.