Our Doubled Side Mattress topper Adds two levels of comfort, with one side being firmer then the other with integrated hybrid technology two unique zones of comfort to assure a deep sleep regardless of your desired preference. Zone1 with Cool Flow™ offers a firm therapeutic support that relieves pressure on your body for an enhanced level of comfort. This firm zone also helps keep your spine properly aligned while you sleep, reducing back aches and pain. Zone 2 with Graphite-Gel infused memory foam offers a medium-soft support designed to adjust to your body's contour and weight while you sleep. This foam technolgy alows an enhanced transfer of heat from the body providing a cooler sleep surface.