Our most popular marking pens. Writes on metal & most surfaces including oily or wet surfaces. Suitable For indoor & outdoor use. Oil-based opaque paint. Permanent marks on metal, oily metal, rubber, plastics, composites, wood, masonry, glass, nearly anything. Water-proof and weather-proof. Quick drying - 30 seconds or less. Fade & abrasion resistant. Chemical and UV light resistant. Marks are lightfast.