Outside diameter gauge (metric).

I made several quick check diameter gauges to check the curvature of some existing hardware. These are printed with the full diameter (ø) on the front, and they are stackable using an m4 machine screw and nut.

The center diameter dimension is parametric, so you can change the length of the diameter to make your own gauges. I print them face down on the printer bed for the clearest readable recessed text. Feel free to use them and enjoy. :)