Humbrol Paint base

Since I paint models, I sometimes fear topping the little paint cans. Then I realized I had a recently acquired 3D printer, so I made these.
With Tinkercad, I chose a rounded edge cube of the exact size (above 30mm, the diameter of the cans), then used an exclusion cube and an exclusion cilynder to make it the right size with a hole in the middle.
I prepared six on my Halot Box software then printed it.