Sony M2 Phone Case 1mm thickness

I found it hard to buy a new phone case for my old model Sony M2. It is a good idea to get it 3D printed.

I tried to design the phone case as slim as possible. I used PLA to print with 1mm material thickness.

The case is perfectly fit but I am afraid that it will break easily after a few times of re-installation as the structure is not strong enough.