The Isotonic Iso-Cool, visco-elastic molded foam mattress topper is filled with 11 ounces of luxurious spiral-spun polyester fiber to provide a restful night's sleep. 300 thread-count cotton cover has elastic for a secure fit memory foam helps to reduce tossing and turning Outlast Adaptive Comfort fabric regulates body temperature, absorbing and releasing body heat as needed Sleep Better with supremely plush temperature-sensitive memory foam that equalizes pressure and reduces tension foam pad is 3 thick with a 2-pound density 15 spandex skirt fits mattresses up to 20 deep Back is polyester. Polyester filled cover fits over the foam pad and your mattress. Cover is hypoallergenic and washable; spot clean foam. Manufacturer's 5-year warranty. Made in America of imported materials. Twin topper: 37x72 Twin XL topper: 37x77 Full topper: 51x72 Queen topper: 58x77 King topper: 76x77 Cal. King topper: 70x80 Memory Foam Tips: remove from packaging within 72 hours after unwrapping, air product for a few hours to eliminate trapped odors allow 48 hours for this product to return to its original shape Topper dimensions may be sized slightly smaller than your mattress for a secure fit under your sheets.