Sivan Balance Ball Fit Chairs, 3 Models

Anybody know what the diameter of the ball is, the height of the seat, and whether or not the height is adjustable? All would be useful in order to know if this would fit me, even though they give a wide range of body heights that it’ll fit. Still, my understanding is that having the right fit is crucial for these. Thanks.

Normal chair height. It will depend some on how much you inflate.

It’s noted as designed for users 5-feet to 5-feet, 11-inches tall.

Found this on Amazon.

and this

and this