The Dura 8R has the highest warmth rating of the Dura sleeping mat line. Like its name suggests, Dura is our warmest, most durable backpacking mat for demanding adventures, including extended outings in alpine and polar regions, rugged paddling trips, and overlanding. EXPED's DOWNMAT TECHNOLOGY, with 700 cu in of down insulation for use in all seasons, ensures maximum warmth in any weather, while a 9 cm thick air cushion cradles the body. These air chambers run head to toe, fully supporting the body for an unrivaled night's sleep and giving maximum durability.