Still the top choice for adventurers seeking lightweight and durability, the Therm-A-Rest Z Lite Sol Mattress is warm and comfortable. The new thermal reflective barrier increases overall warmth by 20%. The Sol is the right choice for people seeking ultralight sleep anywhere warmth, durability and comfort. Weighing less than a pound, this mattress goes anywhere easily. Accordion-style design packs lots of comfort into as small a space as possible. Closed-cell foam is incredibly durable, providing an exceptional value and many years of worry-free performance. All-new proprietary foams are softer on top for extra comfort and denser on the bottom for extra durability.