The Z Lite SOL™ mat is the lightest, most compact closed-cell Therm-A-Rest mattress. The Z™ Lite SOL features a compact accordion-style shape, heat-trapping dimples and a reflective ThermaCapture™ coating that helps capture radiant heat, increasing overall warmth by nearly 15%. The proprietary foams are softer on top for extra comfort and denser on the bottom for extra durability. Wherever you’re headed, a Z Lite SOL mat is the right choice for ultralight warmth, durability and comfort. I started using this mat during a winter training in 2013 and always carry one in the bow hatch of my kayak: to comfortably sit on rocks at lunch time, in case of an unexpected overnight stay or to provide a good insulation when treating a casualty. In cold or hot weather.