This case is intended for use with the Kindle Paperwhite 11th Gen (2021 edition). It might work with other Kindle models, but there are a lot of variants out there with small but significant differences. If you decide to print this case for a different version of the Kindle, you do so at your own risk (But if it works, I'd appreciate you report this in the comments).
Material: I printed this in PLA, and this works fine (see pictures), but I suppose PETG or something else would work too.
The link hinges are a tight fit for the filament, so I ended up drilling out the holes just a tad to make life easier.
If the filament does not stay in place through friction you can heat up a knife and press the side of it against the ends of the filament to slightly melt and flatten it. This will make it wider so it cannot slip through the holes anymore.
In the photo you can see I improvised 2 magnets to keep the cover closed. They are super-glued in place. I did this because I was in a hurry. A better way would be to get the proper size magnets, or customize the holes to properly fit the magnets you have.
The author remixed this model.
The bottom shell in the original model has some issues:
The result is not perfect, since there are some remaining artifacts, but the slicer reports no errors and after slicing these artifacts are gone.