Duncan CNKIT-9 Concepts Underglaze Primary Colors Paint Set, 6 Best Selling Colors in 2 Ounce Bottles with Free How To Paint Ceramics Book Concepts Underglazes have a versatile formula that allows for translucent designs with one coat and solid coverage with three coats. They are nontoxic and food-safe with the application of three solid coats or when a food-safe clear glaze is applied over them. Can be brushed, sponged, spattered, or stenciled onto ceramic bisque. Kiln Fire to cone 06. Made in USA. Includes free How To Paint Ceramics Booklet published exclusively by Wholesale Craft Outlet.