We zoned this layer to provide more softness for the shoulders and legs, but used a higher ILD latex foam where the hips and low back are to add a greater support for that heavier area of the body.  The top layer is two inches of our extra plush 4lb. density memory foam that wonderfully plush feel.  The second layer is the highest quality 5lb. memory foam, followed by the 3 inches of zoned Talay latex foam that has a medium firmness which adds more support, while retaining a comfortable feel and transitions into the extra supportive fourth layer, the very firm high resiliency polyurethane base at 40 ILD.The Soft-pedic™ uses our specially designed hand stitched hypoallergenic, stretchable terry cover that is easily removable for washing.  It has a special breathable design that will ventilate better than most covers to keep your body temperature constant, so you will not have to worry about this mattress getting too hot.  The Soft-pedic™ mattress is soft enough to contour to the bumps and curves of your body, but firm enough to provide proper support and will never bottom out.  While the Soft-Pedicä was specifically designed for side sleepers, it can also work well for back sleeping.  However, we usually recommend the Tri-Pedic for a pure back or stomach sleeper.  The Soft-Pedic comes a as 9 inch thickness, but we can customize any level of thickness to meet your needs.  We are so convinced that you will not find a more comfortable mattress that we are offering a 4-month trial that includes the option of having us pay for the shipping of another mattress if you are unsatisfied for any reason at all.  As you can tell we are extremely proud of this mattress and want you to experience first hand why the Softpedic™ will be the best mattress you will ever own!