XYZ 20mm Calibration Cube With Holes

Lately I've been seeing a lot of people printing 20mm cubes as forms of calibrations. Which is great to hone in your Outside Dimensions! But why print a bunch of different "calibration" pieces? So as simple as it is (and why I didn't think of this sooner), I bring you my version of the XYZ 20mm Cube. Which can teach you a lot about your own printer! Outside Dimensions, Inside Dimensions, Shrinkage, Retraction, Supports. Not just your plain ol "let me take 3 measurements from a single print" but