Corrosion is the deterioration of a metal through oxidation and is caused by reactive chemical elements, such as halogens and sulphur. The ink in this marker contains only tiny amounts of these elements, thereby reducing the likelihood of corrosion, regardless of the type of surface or the ambient conditions. Waterproof, lightfast ink with a low chlorine and halogen content, quick-drying and with no added toluene or xylene. Adheres superbly to metal, steel, iron, aluminium, stainless steel. The cap can be stored on the end of the barrel so it won't get lost. High-quality aluminium barrel. Made in Germany.