For compact carry on the trail and comfort back at camp, these Klymit KSB bags feature warm, lofty white duck down inside a lightweight, DWR-treated 20d ripstop nylon shell. Soft, durable fabrics and flexible baffles hug your body and eliminate air movement, while leaving enough room in the torso area to maneuver freely and wear a jacket on colder evenings. The KSB’s stretchy design is a favorite among those who move around at night or don’t like feeling confined in a traditional mummy bag. The mummy hood, adjustable neck collar, and half-moon foot box lock in warmth, and the three-quarter-length zipper makes it easy to crawl in and out.