Drink + phone holder with extra stability for SUP (Paddle board)

My parents wanted drink holders for their SUP, paddle boards. But the strings on them was not very tight and on one of them you couldnt really adjust the tightnes. So I made them drink holders with extra stands for that extra stability and threw in a phone holder.
I paddled hard, jumped up and down from the board and no holder managed to fall or spill any drink.

The string locks slightly into place in the bottom.

Both I and X cutouts are available.

I printed in PLA

4 walls 
20% infill (probably overkill)
No support

PETG might be better as it will be out in the sun but it worked well for me when I went out.