The set of Whitmor Spacemaker Storage Bags contains one jumbo, three large bags, four medium bags and four small storage bags. These bags are reusable and can be used for storage and protection against air, moisture, dust, molds and bugs. Once sealed, the items will be protected against air and moisture. It has a no-cap valve that is used to push and create a vacuum inside the bag using any regular vacuum pump. It has a zip closure that seals the contents of the bag. Fabrics and garments, that otherwise take up a lot of space, can be compressed and stored safely in these bags. You can store these bags anywhere from closets to closed attics.