Holder for glass pots

I have glass pots recycled from honey pots and other things. They have the same size and are kind of stackable although they are not exceptionally stable when stacked, which is not so comfortable to have with glass.
So I made a little extra holder to keep them in place when they are stacked, and it is extremely effective.
The characteristics of the pots is that they have a round edge at their base, and the lid has an extra circle to help stack other pots on top, so the holder fits that extra circle to stabilize things. See images.