Eiderdown is the lightest but warmest natural material in the world, and it is extremely rare. The down is collected by hand from the eider duck’s nest after the ducklings have abandoned the nest. The eider duck develops the world’s best down because it lives in the coldest parts of the North Atlantic, where it must adapt to extreme temperatures.
The thermal properties of eiderdown are superior and exceptional. Eiderdown has excellent insulation properties, but it is not for everyone. If you tend to feel hot when you sleep, eiderdown might be too warm for you.