This is holder for tablets that you put on your bike. It fits devices up to 25.5cm width and 0.8mm tall the length doesn't matter but the maximum is around 35cm. I have Ipad (gen. 9) and it fits really great.

You should print it with 4+ wall loops to gain strength also it should be printed with stronger filaments like petg or abs 

I also made higher angle version (that means it will hang more vertically).

THIS IS REMIX

The model I was inspired by: https://makerworld.com/pl/models/60785-bike-trainer-ipad-mount#profileId-148764