• DESIGNED TO FIT YOUR BUM SHAPE AND SIZE: Unlike other seat cushions, the ChiroDoc Orthopedic Memory Foam Seat Cushion was carefully designed with your bum's needs in mind, conforming to the natural contours of the body, no matter what shape or size. Perfect for men and women, young or old, these cushions also help pregnant women alleviate the weight of carrying their baby while sitting.
• RELIEVES BACK AND SCIATICA PAIN: Suffering bums are now a thing of the past. If you are a victim of lower back or sciatica pain, this coccyx cushion can make a world of improvement in your life. It gives you the right support that makes sitting not just tolerable, but enjoyable again. Takes away pain by relieving direct stress and pressure from your tailbone & spine. This unique memory foam cushion prevents numbness and other types of pain brought by prolonged sitting.
•  IMPROVES YOUR POSTURE: Proper posture makes a huge difference when sitting on a desk all day. Stress on your back decreases with the right posture, making you look good while sitting, while helping you avoid injury. It corrects your posture by relieving pressure points and facilitating correct lumbar curvature. It promotes proper spine alignment and helps you get through the daily grind with ease.
• NEVER GOES FLAT...USE IT ANYWHERE : The ChiroDoc Memory Foam Seat Cushion is designed with the highest quality materials to never go flat. It's Memory Foam is softer than other cushions while retaining its form even after extended periods of use. Use it anywhere you like whether on the plane, on long drives and even on hard chairs at home or at work. Many folks even use it on their wheelchair. 
• HYPOALLERGENIC, DUST MITE RESISTANT COVER: Perfect for people who suffer from allergies and asthma. The difference? Our seat cushion has a dust mite resistant cover inside that seals off dust mites from breeding and releasing fecal matter that can flare up allergic reactions. Our main concern is your comfort and rest.

It does hold it's shape and is comfortable to sit on. I have only been using it for 2 weeks to see how it is. So far there have been no problems but with anyone who sits a lot and has a lot of back problems after a while you are going to hurt.

I can say this is a good seat cushion. I was glad that I got to try this product out in exchange for my honest and unbiased opinion.