Revolutionary memory foam infused with cool, rejuvenating gel provides the ultimate supportive and comfortable sleep experience. Gel absorbs pressure and channels heat away, preventing excessive heat build-up that causes sleep disturbances. Type: Gel memory foam 4 inches thick Density: 3.2 pounds Originally designed for NASA, this space age foam cradles the body, reducing pressure points that cause tossing and turning Adjusts to body temperature Draws uncomfortable warm air away from body Includes 300 thread count Egyptian cotton cover with 17-inch skirt Eliminates motion transfer Disperses weight evenly Helps rejuvenate tired muscles and eases back pain Meets all flammability standards Dimensions Twin: 37 inches wide x 73 inches long Full: 52 inches wide x 73 inches long Queen: 58 inches wide x 78 inches long King: 75 inches wide x 78 inches long California king: 70 inches wide x 82 inches long Memory Foam Tips: Remove from packaging within 72 hours to maximize foam expansion. This product arrives very tightly packed. Unwrap and allow 48 hours for product to return to original shape. Being sealed in plastic packaging sometimes traps odors. After unwrapping, allow to air for a few hours. Due to machine-cutting manufacturing processes, there may be slight variances in the dimensions. The firmness level of every item is unique. Please be advised that even similar products may produce different firmness results. Topper dimensions may be slightly smaller than mattress dimensions. Size has been designed to allow easily securing fitted sheet over new memory foam topper.