A tough marker for tough jobs, the Solid marker is solidified paint in a marker stick. It marks through oil, grease, rust, mud, snow and more -- great for inside or outside use. Just twist the end to advance the paint when you are ready to use more. Capable of a wide range of mark sizes from fine (4mm or 1/8") to broad (13mm or just over 1/2") by varying the amount of pressure applied to the marking stroke. Ideal for use on wood, cloth, canvas, plastic, steel, iron, rubber, cardboard, glass, fiberglass and concrete. Certified nontoxic solid marker is highly permanent, non-hazardous and low odor Details:Available in multiple colors13 mm tipFast drying and nontoxicWaterproof, fade resistant and chemical resistantIndoor/outdoorPermanentConforms to ASTM D 4236Alcohol based cleaners will remove the ink from most non-porous surfaces