heavy duty lightweight luggage and efficent travel bag for your next trip? Look no further. Check out our hyper-efficient reinforced collapsible and expandable wheeled travel duffle bag. It's a mouthful to say, but the features aren't short-lived! The duffel bag has a two-tiered zipper that allows you to expand the bag to almost twice its original height, giving you nearly twice as much storage space. When not in use, simply zip up the levels to "collapse" the walls. On the outside, you have zippered pockets to store anything you need on the fly.