Set of 4 Comforter Duvet Donuts. Prevent Bunching & Shifting of Comforters and Duvets, Keep Comforter Corners in Place. Fits types of Duvets and Comforters Without Harming Fabric. Prevent Bunching & Shifting of Comforters and Duvets. Keeps Comforter in Place. Fits All Sizes/types of Duvets and Comforters.