About this 3D model

The last nickel calibration test I designed gave no real feedback on how to fix the problem. This one should allow for measurements and corrections.This one is exactly 21.21 mm wide in both the x and y. The slots are the same lengths (21.21mm) but a little wide (3mm)to disregard the width of the slot until the x and y are perfect.Please like and upload photos of your made thing! I love to see this still working for everyone so many years later!Check out my interwebs!https://www.youtube.com/geodroidjohnTwitter- @mrjohneckerBuy some 3D Printers-Gearbest- https://www.gearbest.com/3d-printers-3d-printer-kits-c_11399/?lkid=13099383