This small, ultra-lightweight packsack protects your belongings against dust, dirt and moisture, or pack wet things to protect the dry things around. Just put your things in, roll over the top of the bag three times and seal with the buckle. The material and the sealed seams are water-repellent. And a little air inside the bag provides extra protection for the items inside. Incidentally, the packsack can also be attached to the outside of a backpack or used inside as an interior pouch.