I am particularly short and was recommended to sit on an exercise ball instead of a chair after I hurt my tail bone. However I found that to get a ball big enough to reach my desk I couldn't stay balanced on the ball and would have to fall off to get away from my desk. I found this product at a local "back" store, and thought for the price I can't really loose - IT HAS BEEN A LIFE SAVER. In the year I have had it not only has by back healed and is stronger, but I just have the BEST ABS EVER as I'm doing a daily 8 hour ab routine just siting on the fitball disk at my desk. I now have a 6 pack and I didn't really even try...

My pregnant boss tried to steal it, she thought it was great. 5 stars

I have sciatica pain with foot drop and needed more time to work on my core muscles. The ball chairs seemed too expensive, and the more affordable ones aren't necessarily height adjustable (my desk is really tall--I'm not). So, I bought the disk cushion and use it on my desk chair at work. While I don't get the reach and flexibility of my balance ball, it provides me with just enough motion and support to make it worthwhile for the price. 4 stars

This disc has helped relieve most of my back pain when sitting at the office. The disc allows you to determine how much air you want in it....less proves more demanding on the muscles when exercising. The disc as a seating tool is wonderful in that it provides a ball of air that lifts pressure off the lower back and allows you to sit with ease. Helps to enhance better posture by forcing you to use your stomach muscles to balance and maintain your position. I was in a ton of pain at work before I got this due to tense muscles and scoliosis....but this has helped tremendously! 5 stars

Item delivered as promised. It's a good product, but doesn't QUITE reproduce the sensation of sitting on a balance ball. Remember, it has some height to it, so you'll need a lower chair, if you use it. I am quite happy with the item, and its versatility. 4 stars

Imperceptible exercise as you sit on this-you tighten & tone your abdomen & back without realizing it.

Great for posture. To use this, you have to sit up in your chair with feet firmly planted on floor. Terrific! Lessen air in pillow easily to increase training. Good for all fitness levels. 5 stars