It is one of the most common bags today, characterized by maintaining a straight posture thanks to the bellows at the bottom. This bag can be manufactured by different laminations, which makes it suitable for use to pack an infinite number of products, just taking care of the materials with which it has to be manufactured. It can have a zipper or hermetic closure at the top so that the client can open and close the package as many times as necessary without affecting the conservation of the content.