My review of the Orthopedic Coccyx Seat Cushion for Office chair & Car Seat
I have bought 2 or 3 seat cushions in the past, via Internet and hard copy mail order catalogs.
All of the cushions flattened when I sat in them, and it felt like I wasn't sitting on a cushion at all.
One cushion, the "Egg Carton" one, I was very uncomfortable with, as I felt I was sitting in a cushion filled with water as every time I shifted my weight, the cushion would move to the left or right.
The result of sitting in the above cushions was pain in my butt after I sat briefly and for a long period of time. Also, none of these cushions had the big hole in the middle to relieve pressure on my butt.
The orthopedic coccyx seat cushion is totally different. It is solid, firm foam that does not flatten. It has a hole in the middle of it, and I no longer feel like I am "sitting on nothing." My butt no longer hurts.
My only regret is that I wish the cushion was a bit bigger. But I am very happy with it.