Evolis R5F008AAA YMCKO ribbons consist of yellow (y), magenta (m) and cyan (c) panels for printing a full spectrum of colors by combining the colors using varying degrees of heat. The k panel is a black resin panel, typically used for printing text and barcodes and the o panel is a thin, clear protective overlay that is applied over the entire surface of your cards. Evolis r5f008aaa ribbons are especially back-coated to extend print head life.