ZCORR manufacture storage & preservation bags for firearms and ammunition. The outside layer of the bags prevent moisture and oxygen from getting in. The inside layers are coated with a chemical that adheres to the metal of the gun inside, preventing corrosion. If opened frequently they will retain their anti corrosion properties for 5 years. If opened infrequently, they can last up to 20 years.
The bags come in a variety of sizes for ammunition, pistols and rifles.