Sometimes you need to carry a little extra, or want a smaller bag for on-the-ground adventures, but don't want to check a bag. Packable travel bags allows you to do both.
Bring a packable daypack (packed flat in your carry on bag) in order to explore a new city. If you have a bit of luggage overflow on the second leg of your trip, fold the duffle into an envelope-sized rectangle and pack it flat for one-bag travel.
A packable travel bag allows you to explore on your terms.