631eb7f1__about_the_Visa_Waiver_Program__Field
[Description] Enter the billing postal code of the credit card. A U.S. Zip Code format must be 5 or 9 digits (no dash). A Canadian Postal Code must be in the format AnAnAn, where ‘A’ is an uppercase letter and ‘n’ is a number. A Mexican Postal Code must be 5 digits. [Field] 
Postal/Zip Code
Everything you need to know about the Visa Waiver Program
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