If you want to save as much weight as possible without sacrificing warmth and comfort, there's no getting around the Ohm 20F/-6C. The Ohm weighs only 635 g. It is ideal for outdoor adventures in cold seasons. With spacious dimensions and the ability to transform into a quilt for two people. The fill is fluffy 900-cuin Nikwax Hydrophobic Down with the best warmth-to-weight ratio and moisture-resistant insulation that dries quickly and compresses small. Thermally efficient chamber construction maintains consistent heat distribution, while insulation zones add extra warmth to key areas. Ultralight outer material and extra fluffy down ensure a low overall weight and a particularly small pack size. A full-length zipper, unique in this class, extends around the foot warmer pocket, so the sleeping bag can also be used as a convenient, flat-opened quilt on warmer nights. Two fully opened Ohms can be zipped together to form a cozy double sleeping bag. The design of the Ohms is based on premium materials and quality features from Therm-a-Rest. It is feather-light and versatile without sacrificing performance.