These are refills where you set it into your passport size TRAVELER’S notebook. The size is the same as the passport you carry when traveling, so it makes it easier to carry it around. Try writing down things you see, or ideas that come up to your mind. By inserting a zipper case or a file, you can even use this passport size as a wallet, card case, or even as a passport cover. Please choose your favorite refills, and discover your way of using it.