Suffering coccyx for years, I decided to invest on different cushions to relieve. The latter is correct on a chair. For the couch, I would not recommend it because it can not be well placed in the couch and on the cushion. It is true that the fabric too tight little lessen the effects of the cushion. The foam is very rigid, a big plus for that. One can sit on it without fear that it collapses. For me, I will say that it has a diameter too large for optimum use, the central hole is not big enough for me to wedge myself without my coccyx rests on the edge of pudding.