Teflon-coated fiberglass, cut in rounds to fit racks and turntables make the greatest baking sheets. Use on racks like baking pans or on oven floor or turntable as a liner to keep oven clean. Just wipe off or wash in soapy water and store rolled up in paper towel tube. Reuse hundreds of times. Useable for microwave, convection or combination heat. 11.5-inch round. Withstands heat to 650 degrees.