What is the Endy Duvet’s fill? Administrator 23 January 2020 15:12 Updated The Endy Duvet uses premium down alternative fill made from polyester fibres for perfect, all-season warmth and comfort. Related articles Will the Endy Duvet fit in my washer? Is the Endy Duvet good for all seasons? Do I wash the duvet before I use it? Why is the Endy Duvet quilted? Can the Endy Duvet be used with other mattresses or duvet covers?