the ball is great, sturdy, not hard to inflate -- but it is not 65"! I measured it every way i could think of, including using the tape thing provided with the ball (ostensibly to prevent over-inflation). I definitely ordered the 65-incher and the packaging says 65"; and it's green (they are colour coded by size) so .... weird. I can still use mine for exercise but I was hoping to use it to sit at a desk and work at a laptop too, and its a bit low for that.
Very strong material, comes with spare plug ( which is great) easily supports 200 pounds a good buy at this price.