STAEDTLER Lumocolor omnigraph Box Contains 12 crayons. Staedtler Omnigraph crayon is a universal dry marker for almost all surfaces. Writes on surfaces such as paper, card, stone, glass, plastic, china, leather, fabrics, metal and wood. Even writes on dry wood. Hexagonal paper-wrapped crayon, 12mm diameter, 133mm long. Waterproof and UV-resistant.