The Mountain Hardwear Ratio Sleeping Bag ensures a sound sleep from dusk to dawn so you can get the most out of your backpacking or camping trips. ThermoTrap Baffle construction secures 650 fill down insulation in smaller chambers to balance the down evenly across the entire bag, and the down insulation's Q. Shield treatment helps the down resist moisture and retain its heat trapping loft, to keep you warm in sub freezing temperatures. Its comfort mummy cut provides a slightly larger shape than standard mummy bags to keep you comfy without adding weight or minimizing warmth. Mountain Hardwear made the Ratio's shell out of dobby for durability, and the taffeta lining is smooth to the touch for extra comfort. The down filled face gasket at the hood and the insulated draft tube across the zipper make sure you don't feel a chilly draft throughout the night. The hood features single handed drawcords that cinch it securely around your head with a simple pull.