Volatile corrosion inhibitors are materials that prevent corrosion from their vapour phase. Rust destroys valuable metals. Corrosion, and its consequences, causes damage amounting to billions of euros every year.
This is unnecessary. Rust and corrosion have no chance when the right packaging is used.
The active chemical evaporates from the carrier material and deposits itself in molecular form on the metal parts to be protected. This prevents a reaction between oxygen and the metal surface. The material also gets into difficult-to-reach areas and even penetrates cavities, drilled holes, inner threads, etc.