Rugged, puncture-resistant backpacking mattress. ° Puncture-Resistant: Integrated open- and closed-cell foam construction protects against punctures. ° Backup Comfort: Even punctured, mattress continues to provide essential warmth, comfort, and performance, with the same R-value (3.2) as a ProLite 4™. ° Lightweight: Light and warm enough for everything from thru-hiking to expedition use. ° Stuff Sacks: ToughSkin small fits in a Trail Lite™ Stuff Sack regular and Waterproof Stuff Sack™ regular; ToughSkin regular fits in a Trail Comfort™ Stuff Sack regular and Waterproof Stuff Sack regular. Uses: Ideal for use in thorny environments, desert and winter camping, and expeditions. Therm-a-Rest has pioneered an array of technical breakthroughs, from first-of-their-kind die-cutting technologies to a proprietary method of bonding foam to fabric that’s so durable we can guarantee it for life. Our latest innovation is the puncture-resistant construction featured in our ToughSkin™ and Ambush™ mattresses. From researching mattress performance, we know that thorns are the primary cause of punctures. To combat this problem, we developed a design that sandwiches the mattresses’ air-holding seal between a top layer of open-cell foam and a bottom layer of closed-cell foam, then joins them all with our guaranteed foam-to-fabric bond. Because the air-holding seal is protected by a bottom layer of closed-cell foam, the resulting mattresses are extremely puncture-resistant, eliminating 95% of thorn-related punctures while also providing unprecedented protection from sharp rocks and other debris. And, in the unlikely event of a puncture, these mattresses continue to provide essential warmth, comfort, and performance.