Gel Highloft 4-inch Memory Foam Mattress Topper with Cover (Twin) Type: Gel memory foam Measures 4 inches thick Density: 3.2 pounds Queen: 58 inches x 78 inches King: 75 inches x 78 inches California king: 70 inches x 82 inches Memory foam is resistant to dust mites and is naturally antimicrobial Originally designed for NASA, this space age foam cradles your body, reducing pressure points that cause tossing and turning Temperature sensitive foam adjusts to your body temperature Draws uncomfortable warm air away from your body Open nature of textured side provides improved air flow Includes 300 thread count Egyptian cotton cover with 17-inch skirt Eliminates motion transfer and uncomfortable pressure points Meets all flammability standards