This yoshi's egg design is a Nintendo Switch accesory, which can accomodate 12 Switch game cartridges!
This article contain :
STL model of every parts.
2 useful PDF documents which explain how to assembly the model and how to print it ! These documents include, an introduction of the model, 2 advises to print it in a proper way, and some idea to upgrade this egg !
A purchase of magnets is not mandatory but recommended to obtain a fully finished result ! (more detail in documents !)