You can hardly get a better warmth-to-weight ratio than the Mountain Equipment Firelite down sleeping bag. The sleeping bag was specifically designed to be extremely lightweight with optimal thermal efficiency. This bag is thus best suited for those who want an ultra-light pack for fast mountain activities. For alpine adventures, the bag's thermal efficiency is sufficient for the most part, but in the spring and autumn, the bag should be used at lower altitudes. With this in mind, the sleeping bag is great for ultra-light tours, trekking, hillwalking, fast hiking or trail running. Thanks to its light weight and small pack size, it'll fit in any rucksack. The sleeping bag is filled with high-quality Russian goose down. Thanks to the alpine fit and the integrated EXL system, the loft and thus the bag's thermal efficiency have been improved. The outer material and the lining feature the particularly lightweight and breathable Plasma fabric. This fabric is also tearproof and down proof. Of course, the Mountain Equipment Firelite sleeping bag comes with a waterproof stuff sack to keep it dry as well as a cube for storing the bag between tours. The Mountain Equipment Firelite down sleeping bag is a great bag for ultra-light travels.