This is a minimalistic design with space efficiency in mind combined with rounded sides on the inside to facilitate picking up whatever is inside. Magnets are incorporated on all sides to secure connection between cups. Insertion of these magnets is optional however. 

Three versions are available with one to three segments. 

The cups dimension are 15/25 mm height and the distance between two parallel sides is 100 mm (side length: 57.7 mm). 
 

Magnets:

These cups are designed for diametrically (!) polarized magnets (polarized towards curved sides) with a diameter of 3 mm diameter and a length of 6 mm.

For example available here: 

[https://www.aliexpress.com/item/1005005084877072.html](https://www.aliexpress.com/item/1005005084877072.html)

Those magnets are a bit more expensive than regular ones but super easy to insert during print as they stick to the bottom of the print and always orient automatically in the right direction in the finished cup. You can store the cups also on a fridge if you have the strange inclination to do so ;)

Print advice:

I printed this with Prusament PETG and Extrudr PETG and both work fine with Slicer standard settings. The amf file comes with variable layer height for nicer curve results and G-code enabling a pause when it is time to insert the magnets (continue print with single click on printer dial). If the nozzle temperature is changed for using other filaments than Extrudr PETG, the temperature also needs to be changed in the pause G-Code.