The Zipsak Boost Max starts off as an easy to store pouch, transforms into a smooth rolling 5-wheeled carry-on, then expands 11 inches upwards, converting it into a large check-in bag! Our custom sized Zipcubes add structure to the bag and enhance performance while providing even weight distribution. When not in use, the Zipsak folds neatly for storage under a bed, on a shelf, or in a drawer. The Zipsak is made from extremely durable, tear-proof, and water resistant nylon fabric.