I bought this because the futon mattress (purchased from a different outlet) was thin and had hard plastic oddly shaped buttons that held the mattress fill in place.  Point been between the metal frame thin mattress and those things it was painful to sleep on.  THIS memory foam is awesome!! I followed the instructions and let in lay flat for the duration specified in the instructions, placed it on top of the mattress and then encased them in a mattress cover.  The futon will still fold up to the couch position and is much more comfortable.