Save your money!
I was using a memory foam coccyx pillow which I loved but, I wanted to try something new.  A co-worker told me about this cushion, and was a little hesitant because of it's price but, the videos online were so convincing so I bought it. The cushion is heavy and the case looks like it's too small but, it DOES fit!  I thought it would feel squishy sitting on it but, it's quite firm, and definitely takes time getting used to it.  The cushion stays on my office chair with no problem with the rubber bumps but, the top is a little slippery when I try to move my chair forward/backward.  The whole concept of this is excellent, as they say, &#34;Seeing is believing.&#34;  But, I've been sitting on this for a good 2-3 months now and it's not that comfortable.  My butt hurts after a few hours and I actually feel pain in my lower back.  My guess is because there is no cut out for your coccyx.  I've switched back to my coccyx pillow and it's way comfortable.  This was an expensive mistake but, at least now I know. Here's the coccyx pillow I use.  [[ASIN:B00J4VIN1O TravelMate Coccyx Orthopedic Gel-enhanced (Medium-Firm) Comfort Memory Foam Seat Cushion]]
Rating: 2 stars