I designed this case for my iPhone 14 Pro Max when I first got it and was waiting to buy a regular case. I printed this in Ninjaflex TPU (85A shore hardness), which works well. Something in the low 90A scale would be better in my opinion as this was a little too flexible and felt like it could slip off easily.
The case is thick enough so that the camera lenses are protected when you set it down on a table or flat surface.
I wouldn't recommend printing this in a non-flexible filament.