The screw rusts easily and after a while you can't tighten it when the support doesn't hold the shower firmly. I suggest that when you install it, you seal the screw with a bit of silicone so it doesn't rust. If tightening is needed, the silicone won't be a problem.

The only thing that bothers it is a shape that shows that you are pressing the circle to open it (inside are the screws). I had to make a hole from above because the holes were not the same. It is suitable for heavier phones as well. I recommend it!