The region shows the approximate area where the card can be used; the area must be greater than 5 square miles. German American Card Control can typically map the transaction down to a ZIP code or city. If the city or ZIP code of the merchant overlaps with the selected region in the map, then the transaction can still go through. There are instances where a merchant location cannot be mapped down to a ZIP code or city, in which case Card Control will default to a state-level match.