The MontBell U.L. Down Inner Jacket weighs less than most cotton Tee-shirts, blocks an amazing amount of wind, and is warmer than most heavy fleece jackets, while compressing to the size of a 32 ounce water bottle. Specifically designed as a replacement for the heavy and bulky fleece garments used by many backcountry enthusiasts, the U.L.Down Series is what you need when warmth is critical, minimal weight is paramount, and space in your pack is at a premium.MontBell U.L. Down Inner Jacket Features: Single-quilt construction for weight reduction100-wash rated Polkatex DWR treatmentHand warmer Pockets4/5 c Full ZipperStuff sack includedMaterials: Shell: 15-denier Ballistic Airlight nylon Insulation: High quality 800 fill power hypoallergenic goose down Weight: 6.1oz