The Tension Mummy 500 is a mildly heavy weight high insulation down bag constructed in the comfortable “mummy” shape that provide a roomy and comfortable nights sleep. The bag is made for any trip to the outdoors where the temperature will drop to freezing cold, and the lightweight outer casing fabric keeps the weight down while still providing a durable sleeping bag. The full length zipper is down covered to keep the hot air inside the bag where you can enjoy it, and the adjustable contour hood gives the bag a good feel if you sleep with your head inside it.