Buy Factory Direct and Save! Save Hundreds off Department Stores and Big Chain Store Prices. All Our Mattresses Are 50 to 75% Off Retail Prices. LOWEST PRICE GUARANTEE - Find The Same Mattress Anywhere Else and We'll Beat it! GUARANTEED! Memory Foam (Viscoelastic) Mattress Memory foam (viscoelastic) mattresses use a high-density polyurethane foam as the support system, in the upholstery layer or both. This foam contours closely to the shape of the sleeper. Gel Mattress Gel mattresses use foam that contains gel in the product’s support system, upholstery layers or both. The gel is added to the foam using different types of technology. The gel foam can offer consumers different comfort, feel and heat dissipation features.