The Snugpak Basecamp Ops Sleeper Extreme offers extra warmth and insulation on extremely cold nights. The comfort temperature rating for this sleeping bag is 19 degrees Fahrenheit but can go as low as 10 degrees Fahrenheit for experienced users. The Basecamp Ops Sleeper Extreme will ensure you stay warm in cold conditions with Isofibre insulation. Isofibre is a siliconized hollow fiber fill; this innovative structure traps warm air between the cavities in the fiber and retains heat even when wet and prolongs the sleeping bag's life. The unique structure of Isofibre insulation allows the sleeping bag to be washed and packed in the included compression stuff sack for long periods of time without losing its thermal properties. When unpacked, the insulation decompresses and springs back to gain its maximum bulk and warmth. The Basecamp Ops Sleeper Extreme Lite is equipped with an anti-snag 2 way zipper, zip baffle, hanging dry tabs, a draft collar, and a snug fit hood. The mummy shape of the sleeping bag is designed to retain body heat and does not zip open to form a blanket. The sleeping bag's dimensions are 87 inches long by 31 inches wide; packed, it is 12 by 10 inches. It weighs 4.63 pounds and will add some bulk and weight to your pack. The Basecamp Ops Sleeper Extreme also features AQUALight 190T polyester shell fabric that offers superior water repellence to keep you dry in inclement weather. The Basecamp Ops Sleeper Extreme offers practical features that will keep you warm and dry in extremely cold conditions.