Our toppers are manufactured from a very high density, but soft Memory Foam and are covered with a soft stretch fabric. Memory Foam is unique in two ways: unlike standard foams that compress and spring back immediately, Memory Foam cells compress fully and spread the air pressure to adjoining cells and on the release of pressure, only gradually return to their original shape. This accounts for the way the foam absorbs pressure and thereby reduces strain on pressure points. It also allows the foam to gently conform to your body's shape. The other unique quality of this foam is that it is temperature sensitive, meaning that at lower temperatures it is hard and at warmer temperatures it is soft and gel-like. This quality accounts for the melting feeling that you get when lying on Memory Foam, and accentuates the moulding to the body effect, as a result of the body's natural heat.