The Marmot Nanowave 35 Sleeping Bag is a synthetic sleeping bag for cooler temperatures. Marmot Spirafil high-loft insulation keeps you toasty and comfortable while remaining compressible and lightweight. This mummy shaped bag has a soft lining for coziness and a durable outer-fabric for longevity. The two-way double zipper allows you to vent your feet or your torso whenever you need air. It won??t take up much space due to the compression style stuff sack, so easily take it on your next trip to the great outdoors.