Most spectrophotometers are designed to hold a 1 cm cuvette with outer dimensions of 12.5 X 12.5 mm, however it is often desirable to use a cuvette with a shorter path-length. This thing generates an adaptor that will stably position cuvettes that are thinner (in the beam path dimension) than the typical 1 cm pathlength cells in a spectrophotometer. (The current version assumes that the cuvette is just as wide as the sample compartment in the dimension perpendicular to the beam path.)The included .stl and default customizer settings are for adapting a 1 mm cuvette (Starna, 21-G-1) to a typical 12.5 X 12.5 mm spectrophotometer sample compartment. For generating an adaptor for any cuvette using Customizer measure the outer dimension of your cuvette along the beam path. Then measure the sample compartment of the spectrophotometer you are adapting it to. The bottom thickness can be adjusted to accommodate different beam heights of various instruments. The current version of the .scad file assumes the cuvette is as wide as the sample cell holder.