Zerust VC2-2 NoRust Vapor Capsule - Pack of 4 Use Zerust No Rust Vapor Capsules for Gun Rust Protection During Storage Zerust No Rust Vapor Capsules Protects Metals Against Corrosion Zerust No Rust Vapor Capsules Protects Metals Against Rust Place Zerust vapor capsules inside tool boxes, utility drawers, tackle boxes, knife drawers One VC2-2 capsule protects a radius of 2 feet for Two years.