Zerust products work by releasing a harmless, non-toxic, odorless, colorless vapor into the air around your metal item. Protective molecules settle on all exposed metal surfaces, forming a very thin protective layer that is just a few molecules thick. This molecular layer inhibits electrochemical reactions on the surface of the metal that cause corrosion. Exposed metal surfaces protected by Zerust benefit from a long-lasting shield against rust, tarnish and corrosion.