The Sea to Summit Trek Down Sleeping Bag is a versatile down bag for all types of outdoor activities, including camping, backpacking, and trekking. The mummy style features a shaped hood and zipper draft tube to keep the cold out and the warmth in. Lofty 650 fill power duck down insulation (Responsible Down Standard certified) is treated with a non-PFC Ultra-Dry Down treatment to improve reaction to moisture, retaining loft and performance in rugged conditions. The relaxed mummy shape offers more room between the hips and knees for a natural sleeping position, while vertical baffles over the chest prevent the down fill from shifting during sleep. The Free-Flow Zip system allows you to open the bag sequentially for ventilation up to the point where it is opened flat as a quilt - you can even secure the snaps around your shoulders, open the footbox zipper and 'wear' the Trek around camp. The shell is made from recycled 20D nylon. The Sea to Summit Trek Down Sleeping Bag is available in two sizes: Regular (max user height of six feet) and Long (max user height of six feet six inches) and three temperature ratings: 30-Degree, 15-Degree, and 0-Degree. Includes Ultra-Sil compression sack. Sea to Summit products are guaranteed against defects in materials or workmanship for the lifetime of the product.