Test tube stand for up to 7 normal sized test tubes

This is a remix of my other test tube stands. This version supports tubes with a diameter between 15 and 18 mm and a height above 95 mm. The most typical test tubes I know are about this size.

Version for 7 small tubes: https://www.thingiverse.com/thing:2460058
Version for 7 large tubes: https://www.thingiverse.com/thing:2460095
Version for a single large tube: https://www.thingiverse.com/thing:2460016

I also made a stand for round-bottom flasks, which can be found here: https://www.thin