The edding 8850 Carpenter Pen is equipped with an extra-long and fine nib, stroke width of 1mm. The quick-drying ink is waterproof and smudge-proof. Designed for permanent marking in hard to reach places, on almost all materials that are dust free, e.g. metal, stone, glass, wood, plastic. Its very long and narrow mouthpiece (20mm) means that the pen is particularly suitable for use as an assembly aid when dealing with hard-to-reach places, e.g., drill holes when fitting shelves.