My first attempts. One challenge for me is to make the bars between the holes as thin as possible. At the moment I'm at just under 3 millimeters.

For all those who have a 3D printer, I have designed a special egg adapter. There are pictures of it in the gallery. Do you need it? Absolutely not! Does it look cool? Absolutely yes! You can download the stl files here. It's the main part and a flexible rubber-like support, a ring so that the egg doesn't slip. Good luck!