This heavy down Sferra duvet is designed to cocoon you in sweet dreams. The Sferra Down Collection boasts an amazing variety of down duvets and sleeping pillows. Carefully constructed of down clusters, which interlock and trap air to keep you warm, but also have the remarkable ability to keep you comfortable, Sferra down offers varying levels of fill power to customize the perfect sleeping experience. A measure of efficiency, the higher the fill power number, the better the down and the greater Sferra Cardigan Heavy Down Comforter, King-Home