The box of this cover reads FIT ROUND POOL 3.05m, with the size repeated alongside as 305 cm. That is the diameter of the round above-ground pool Didak Pool cut this cover for.
A cover like this does one thing, and does it without fuss: you lay it over the pool after swimming, let it fall over the top rail and leave it there until next time. Leaves, grass and dust mostly stay on top of it instead of floating in the water.
The packaging contains the cover and nothing else. The pool in the picture is there to make the shape and the fit clear and is not supplied. So measure your own pool before you order.
Meant for anyone who already has a round 3.05 m above-ground pool in the garden and wants to be able to leave the water alone between swims.