We love an Indian summer as much as you do, but sometimes the fringe seasons arent as ideal as you want. Thats why the Marmot Never Summer650FP Down Mummy Sleeping Bag has water resistant down, rated for temperatures as low as zero degrees Fahrenheit, ensuring warmth amidst the vagaries of shoulder season weather. Designed with a slight weight and more compressibility, the Never Summer is an ideal choice for trips, climbs and treks when sub freezing weather is imminent. Insulated with certified 650 fill power down with Down Defender to improve water resistance in wet conditions. Shell is 30d 100% nylon ripstop DWR 1.5 ozsq. yd. Lining is 30d 100% nylon DWR 1.27 oz.yd. Anatomically designed footbox with wrap around construction increases warmth. Full Length locking YKK two way zipper with anti snag slider and zip guard reduces fabric snagging. EN Tested: Comfort: 12.7F 10.7C Lower Limit: 1.2F 18.4C Extreme: 39.6F 39.8C Down filled collar with easy access draw cord. Nautilus multi baffle hood. Internal stash pocket and heater pocket in footbox. Snagless insulated draft tube. Ground level side seams. Hood draw cord. Zipper garage. Stretch tricot baffles. Two hang loops. Stuff and storage sack included.