Therm-A-Rest Z Lite SOL Sleeping Pad is one of the most popular foam mattresses ever! Iconic product used by climbers, mountaineers and outdoor lovers, it will accompany you on your adventures making you sleep peacefully! Made of foam it is very light and practically indestructible. In addition, the density and type of foam varies depending on the area, the upper part is softer so as to be more comfortable, while the lower one is harder and more resistant.The particular dimpled design combined with the reflective ThermaCapture coating, which captures radiant heat and increases the overall heat by almost 15%, means that the Z Lite SOL reaches an R value of 2.0. This makes it perfect for use on its own in warmer climates or as an additional layer when it's colder. Therm-A-Rest Z Lite SOL Sleeping Pad