Whether you've hiked miles down the trail or you're sleeping a few feet from your car, the Mountain Hardwear 15 Degree Down Rook Sleeping Bag is designed to help you get the best night's sleep you can. Its 650-fill down insulation lofts to form an insulating barrier between you and the chilly night around you, while a DWR finish sheds any condensation to prevent it from collapsing the down. The women-specific design means this version of the Rook has extra insulation in vulnerable areas to prevent heat loss, while still maintaining the mummy shape which makes it lighter weight and more efficient.