This is the most simplified 2x2 variation of the Auxetic Cubes, with only 4 squares, each 18x18mm. Good test before printing larger structures, or as a general calibration test.
Printing Guidelines
Fairly loose requirements, just make sure your printer isn't overextruding and has decent cooling so none of the parts fuse. I used 0.16mm layer height, 3 shells. No supports!