My mattress is a queen size mattress. It started out firm but not hard. It was comfortable and supported my back. In less than a year it started to get sags and dips in the foam top. This is a non-flip mattress and all I could do was sleep in different spots to try to allow time for the foam to remember its original state.

I guess it ended up getting dementia because I am ready to throw it out now. I will never buy another one like it. The material was water resistent and easy to clean. It did not remain firm for the length of time expected and for the high price paid did not live up to expectations.