Expedition Polar bag Suitable for extended use in exceptionally cold climates at the polar regions and high altitude mountaineering. Designed solely to provide maximum warmth its no wonder the British Antarctic Survey use our bags on all their deep South Pole expeditions. Double Box Wall Construction throughout eliminates down shift and cold spots Pertex® Endurance Shell; resists condensation and spindrift, protects the all important loft of the design and helps to reduce heat loss Pertex® 4 lining provides the user with a comfortable yet slightly more durable fabric lining next to the skin 96% Polish white goose down, fill power 750+EU/850+US Endurance Hood Cowl and 3D-neck baffle to keep spindrift out Internal Mesh pockets for water bottle and food storage Short two way YKK zip, with the added protection of a fixed gusset gives the user greater room for getting in and out Built in stuff sac, which provides both a storage sac and also protection to the base of the sleeping bag Comfort: -40°C Weight: 2650g