Review on Pharmedoc Exercise Ball Chair With Back Support For Home And Office W/Exercise Yoga Balance Ball, Pump, Removable Back & Lockable Wheels by Joshua Carter

The chair itself is comfortable enough. It does help reduce my lower back pain, which is what you would expect from any exercise ball chair. There are two issues with this chair that I consider to be dealbreakers: the chair itself is too low to the ground and the wheel locks on the casters are very easy to lock on accident.I am 5'6. Proportionally I have a longer torso and relatively short legs, and this chair still has my legs at an uncomfortable angle where my knees are up higher than the seat itself. After a while of sitting like this I get knee pain. Knees should be at a 90 degree angle while seated in a chair.The wheel locks are horrible. Not only does it not make any sense for these casters to have locks (who needs to lock themselves into position while they are sitting at their desk?!), but these ones engage just by brushing up against them. I am constantly reaching around trying to figure out which one is locked so that I can push my chair back to stand up, get files, etc.All in all I'd say that this chair really does not hit the mark and I'd advise that people keep looking for a different product.