The Marmot Womens Helium is an ultralight 15-degree down sleeping bag for women who want it all but dont want the weight. The 850-fill down Womens Helium weighs just 1lb 13oz and packs down super small. But itll keep you warm down to 15F -9C. This bag is shaped for women it has a shorter length and thinner shoulder width than the mens version. In addition, the Helium has increased insulation in critical heat loss areas, so you stay warmer. A down-filled draft tube provides additional heat retention. If youre a minimalist 3-season backcountry traveler, shave off the extra weight and space of bulky unisex bags, and go with the Womens Helium.