Microfiber Size: Full/Queen Duvet Cover Insert - Oversized Full/Queen (88" x 90") Material: Supersoft Microfiber Construction: Ultra Cozy Down Alternative Fill Important Information: Made to add extra comfort to your Full/Queen Duvet Cover Give yourself the gift of unbelievable comfort with our Down Alternative - Ultra Cozy Duvet Insert by Byourbed. This oversized insert is just the bedding you were looking for to fill your favorite duvet cover. Easily machine washable, this duvet insert is filled with the highest grade polyester.