The Big Agnes Blackburn UL 0 Degree Sleeping Bag is a Technical sleeping bag designed for 4-season adventures where weight and packing space Are limited. The 850-fill DownTek; Insulation is ultralight and Highly compressible so it won't hog space in your pack, and it Features a hydrophobic treatment for improved Performance in wet conditions. On the bottom, a flex pad sleeve integrates with your sleeping pad to create a thermally efficient sleep system that also keeps you centered over your pad, even if you do a lot of shifting around at night. Features of the Big Agnes Blackburn UL 0 Degree Sleeping Bag Lightest big agnes system bags offer Technical, roomy sleeping spaces for those who Aren't willing to sacrifice comfort or compressibility Streamlined silhouette for increased thermal efficiency Flex pad sleeve accommodates multiple pad widths Easy on/off stretch-mesh construction is simple Regular and long bags Fit 20in. - 25in. wide pads, wide long bags Fit 25in. - 30in. wide pads Free range hood gives you the freedom to lift your head Jacket-style hood opening contours to the shape of your face for a comfortable, snug Fit Low profile cordlock lets you un-cinch the hood with one hand Pillow barn-keeps your pillow tucked in tight all night Internal hood drawcord gives you a secure, cozy Fit when cinched Non-hooded design on northgate is ideal for summer camping or use as an over-bag Free range foot-box-creates wiggle room for your feet Rectangular shaped bag Downtek water repellent down repels water while maintaining insulating value Anti-snag zipper for a smooth, quick zip Mate together left and right zip bags No-draft collar, no-draft wedge, no-draft zipper Interior fabric loops for sleeping bag liners Exterior loops for hang drying or storage Mesh storage sack and polyester rip-stop stuff sack Insotect flow construction 850 Fill downtek water repellent down Bluesign certified down Fabric Details Nylon rip-stop shell fabric Nylon taffeta lining