Sleep Comfort 4-Inch Gel Memory Foam Flat Topper, California King 100% Cotton Made in US Temperature sensitive foam adjusts to your body temperature Eliminates motion transfer and uncomfortable pressure points Includes 300 thread count Egyptian cotton cover with 17-inch skirt Helps rejuvenate tired muscles and eases back pain Originally designed for NASA this space age foam cradles your body, reducing pressure points that cause tossing and turning