Zerust Plaques are perfect for tackle boxes, pistol cases, gun cases, truck boxes, ammo boxes, tool boxes and more. The capsule provides up to 5 years of anti-corrosion protection. Zerust has proven to be the absolute best way to protect your tackle against rust and corrosion. Molded right into plastic, this patented polymer emits a harmless vapor, forming a protective layer around metal surfaces. All Zerust products will maintain their effectiveness from 2 to 5 years or more, so you can count on hassle free, long lasting protection.