Recommended by Chiropractors. Made of dense, high-quality visco elastic memory foam developed by NASA to support astronauts comfortably in long space flights. This unique material is an extremely high density visco-elastic foam which molds to every curve of the body. This function of the memory foam completely eliminates localized pressure on the body. Localized pressure occurs at the hips, arms, and shoulders, resulting in impaired circulation and numbness, stiffness or pain. By reducing the amount of discomfort, you will experience tension free sleep which is vital to good health. The washable cover is made from the most advanced and comfortable hypo-allergenic fabric on the market. This special fabric has a breathable polyurethane membrane on the back side to protect you from dust mites and other allergens that nest in conventional bedding. This unique cover is Water Proof and it eliminates the need of vacuuming the mattress that is so common with most mattress covers. Twin size bed 75in x 39in x 1.5in.