A simple stand for test tubes by @stellarhopper_137497, but with windows for viewing the contents and legs for stability. I'm using it for home brew samples. The attached .stl is for 14mm standard tubes. No supports, no rafts, infill 15%, PETG or PLA.
The author remixed this model.
Added side windows, legs, and key marker (all optional), added comments into the .scad file.