The natural choice - SpectraFix is a casein-based pastel fixative that protects & holds fragile pastels without changing their colors. Its milk protein & grain alcohol mixture provide you with a non-toxic, workable, fully archival fixative for pastels, charcoal, conte, watercolor, gouache & more. Will not dull colors, dries quickly to an invisible matte finish. Safe for use indoors or in the classroom as it does not have an odor. Conforms to ASTM D-4236 regulations: no known chronic health hazards.