This mummy bag offers amazing performance for its weight. The cut is very lean and spare which saves weight and increases warmth since there are no empty spaces inside the bag to be heated. We don’t recommend this bag for thrashers or for heavy persons who may find it too constricting, but if you can fit inside you’ll never use anything else. Because of its outstanding performance we have used this bag successfully for winter camping. The ultimate combo of lightness, compactness and warmth.