Normally there are two kinds of structures. One is bubble cushioned mailers, the other is epe cushioned ones. It is very useful in our daily life, light, easy and safe to use. It's a perfect replacer of the wood box, carton, and paper mailer in mail service for its quake-proof, compression-resist. It can be used to post tape, cd, cameras, books, cards, and anything that need protect. The inner bubble or epe foam layer can protect the goods from damage during the delivery.