Mitsubishi 7600 Dermatograph Pencils can be used to write on most surfaces, e.g. glass, metal, plastic, ceramic, vinyl, cellophane etc. due to a specially formulated lead. They have excellent resistance to light, are harmless for health and have a shelf life of 8 years, . Unwanted marks can be removed from any non-porous smooth surface. The leads of these Mitsubishi 7600 Dermatograph Pencils are made of wax, talcum powder and pigment, contained in a paper wrapping. The paper wrapping can be removed by pulling the inside thread, which will in turn expose more of the lead. Mitsubishi 7600 Dermatograph Pencils are 17.5cm long with a diameter of 8mm. Writing distance: 2.000-4.000 meters, it differs according to the point load. Line width: 1.00 – 1-4 mm. The price is per piece, commercial packaging is 12 pieces.