A duvet is inserted into a duvet cover. A duvet is a bed-sized bag stuffed with a filling made from down, feathers or wool that provides warm insulation. Some duvets include a synthetic filling that is more suitable for individuals who are allergic to other fillings.
A duvet's size and delicate filling make it expensive and cumbersome to clean, according to Crane & Canopy. When a duvet cover is used, it can be removed regularly for easy cleaning. Covers also can be switched to change a room's decor. Because the cover is easy to wash, some individuals use the duvet and its cover in place of a top sheet.