This case was tested only with the iPhone 6s and iPhone 8, but it is the same size and about the same shape as the iPhone 7 and SE 2020. It may be compatible with the (regular) iPhone 6 too, but it's less likely. Thanks to Adam Vaněk, who test it with the iPhone 8, which I didn't know it was compatible. Please, if you test any of these model give me a feedback of it.
Some of the models are designed for rigid materials and others for flexible ones. The models materials are not interchangeable, so pay attention to the file names. If you have any request on the design just ask me.
2021 is the year when most of country started the covid-19 vaccination; that's why I added a design with the 2021 with the "0" as a virus silhouette and the "1" as a syringe.
For other phone cases check this.
Here is the explanation of the files names:

Flex: made for elastic filaments like TPU. Tested on TPU on the iPhone 6s, thanks to Sam Harford.
Rigid: made for rigid (non-elastic) filaments like PLA, ABS, HIPS, etc. The entire model is a little bigger and the holes for the buttons are opened on the front side. Tested on PLA on the iPhone 8.
Aired: It is widely opened in the back so that the phone can dissipate the heat easily.
Banded: It has regular horizontal grooves in the bed surface, to make the finished texture more regular, avoiding irregularities on that part, and with a better grip.

References

GSMArena

I spend part of my time making these models, letting them available and free for everyone. If you want to support my work, you can contribute with me here:

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