Volatile corrosion inhibiting (VCI) products contain proprietary chemical systems which emit an invisible, odorless, non-toxic vapor which is diffused throughout an enclosure. The resulting VCI rich atmosphere causes VCI molecules to condense on all interior surfaces that they can reach. Metal surfaces inside the enclosure are passivated by the condensed VCI molecules. Vapor Capsules are the oldest member of the VCI family of products. By placing these self contained capsules inside an enclosure, the vapors permeate to every available surface. The condensed VCI molecules passivate iron, steel, copper, brass, and aluminum. The proprietary VCI formulation in combination with ruggedly designed packaging (U.S. Patent No.3,836,077) makes the Vapor Capsules a remarkably practical solution to many corrosion problems.