Sealy Posturepedic Aller-Block Allergen Barrier Cotton Top Twin Mattress Pad Allergen-barrier mattress protection for increased overall comfort Reverse-coated with supple, breathable polypropylene to block allergens ReliaGrip skirt fits mattresses up to 16 inches thick 100 percent cotton cover with 200 thread count Twin Size 75-inches long by 30-inches wide