Many off-the-shelf tube holders and racks are expensive or do not have the exact dimensions needed for an experiment, or both. Meet Labfinity, a system for tube racks and cuvette holders based on the modular Gridfinity design. The base contains insets for 2x6 mm magnets.
The author remixed this model.
Adapted the parametric file to include tube or cuvette holding locations of various dimensions.