My only caveat is that the label is upside down when sitting on the ball.
It does not affect the function or performance so I didn’t take a star off
Measuring tape is accurate. The sand inside is a nice touch when doing exercises that involve picking the ball up. It makes exercises a bit more challenging too since the sand moves around inside.
I’m 5’5” and the 55cm ball is perfect size for me.
I mainly use it to bounce on while watching tv. I do not use it as a desk chair