This is an amazing little product! It cups your sit bones so that they are in more of a position like when you are standing. No more slumping over at the dinner table and at the computer. I haven't felt this good in years. Yes, as one review said, you can just use your own muscles and sit up correctly...that lasts about 30 seconds for me, then I just slump right back. The biggest improvement is when I use it in the truck. Those seats are designed for a large man, not a 5'4" lady. A long trip would now be possible!
I highly recommend this product if your tailbone hurts when sitting. I need to say that it is not as effective on the sofa, but does keep me from ending up sore after some TV viewing.