Featherstone Outdoor El Cordion Insulated R-Value 2.1 Sleeping Pad Closed Cell Foam Mat for Ultralight Backpacking Thru-Hiking and CampingINSULATED & ASTM F3340 Rated: Irradiation cross linked polyethylene foam combined with a dual density heat reflective film traps body heat and circulates warmth. With a standard tested and insulation rating of 2. 1, this foam sleeping pad is proven to keep you warm in the backcountry. MORE COVERAGE: Hexagonal nodes provide 40% more coverage and height from the ground than the traditional egg shell foam pad design ULTRALIGHT & DURABLE: Ultralight