This is another calibration/test cube.
(for beginners in 3d printing: download an .stl file and slice it in a slicer of your choice to convert it in gcode commands for your printer)

Unlike simple cube, it helps you to find out more things about your machine.
TAKE YOUR CALIPERS AND HAVE FUN!

1) Dimensions.
Dimensions of the cube are 20x20mm.
Dimensions of the cube with sticking out cylinders are 21x21mm.

2) Tolerance/Accuracy
Look at holes at the top of the cube. They must be exactly 5mm and 10mm in diameter.
Note that they probably would not be this size because of many factors, but the difference will give you an idea of your printer tolerances.

3) Ringing/ghosting/wobbling
These are common problems with FDM printers, but there are ways to eliminate them.
If the walls of the cube are not perfectly flat and you see waves you can try this steps:
- tighten up belts along walls with vertical lines and round trails on them
- check if your Z-rod is as vertical as possible and does not sway from side to side when rotating
- try smaller speeds.

4) Overhangs
Look closely at side holes, especially at the top of "embossed" and the bottom of "debossed" hole. If you see any problems, try to increase your cooling fan speed or print slower. Note that "debossed" holes may have unfixable "problem" as 1mm is pretty large for overhangs.

After finishing printing the cube, make your adjustments and print yet another cube.

It would be nice to see your comments and photos. Hope this would be helpful.