Ultra-comfy three-season backpacking sleeping bag with adjustable shape and warmth.Customoizable Comfort: Enjoy the spacious feedom of the semi-rectangular bag or the cozy warmth of a mummy bag – pick the shape and temperature that keeps you comfy at night with just a zip. WarmZip Tech: Patent-pending center zipper design zips up to reduce the bags internal space and tuck insulation around the sleeper to boost warmth by up to 10F/6C.Multi-Use Arm Holes: Reach the WarmZip, read a book, play cards, or simply ventilatedo it all while tucked into your sleeping bag for elevated livability.Plush & Puffy: 650-fill RDS-certified hydrophobic down is allocated to key areas with Zoned Insulation for refined heat efficiency and maximum coziness.Eco-Conscious Materials: Shell and liner are made of GRS-certified 100% recycled, soft-to-the-touch nylon and coated with PFAS-free water repellent.Additional Features: YKK anti-snag zippers, cinchable hood, zipper draft