Preventing Liquid Damage To Contents In Mailing Tubes
Tubes used for shipping are usually kept pretty dry. They're in a truck or inside a building for most of the time, and reputable shipping services, including the Post Office, do try to avoid damaging items in their care. But those mailing tubes still have to deal with rain when being carried to and from a building, and there is always the possibility that something in another package can leak (such as shipped medication, wine, and so on).