The Mountain Equipment Women's Helium 800 is a very warm, but light down sleeping bag that was specifically designed to meet the needs of women. Thanks to its relatively light weight and small pack size, the sleeping bag should fit in any rucksack. It is particularly suited for backpacking and trekking in cold but dry conditions, such as in unheated tea-houses in the Himalayas or winter rooms in the Alps. Thanks to the snug alpine fit, the sleeping bag is extremely thermally efficient and light. Plus, it's so comfortable to sleep in. In addition, the sleeping bag is equipped with an integrated collar with a Lode Lock closure, which is easy to open and close and efficiently retains warmth. Of course, the sleeping bag is filled with high-quality duck down. For the outer shell, Mountain Equipment used very light and compressible nylon fabric. This material is not only windproof and downproof but also tough and breathable. Of course, the Mountain Equipment Women's Helium 800 down sleeping bag comes with a waterproof stuff sack to keep it dry as well as a cube for storing the bag between tours.