The ThermalFlare is perfect for backcountry expeditions in cold conditions, when you need the added warmth of PRIMALOFT® insulation. Built for performance in extreme environments, it's large, supportive, and features an ASTM-tested R-value of 4.2, offering excellent thermal resistance to insulate you from the cold ground. This high R-value is essential for staying warm through freezing mid-winter nights. Whether you're fly camping under the stars, hunkered down in a tent, or rolling it out as a backup when the hut's full, the ThermalFlare delivers dependable comfort and warmth. Plus, the durable 40D TPU-coated nylon construction provides extra protection against abrasion.