Global Forever Stamps, Floral, 10 Stamps/Sheet, 2 Sheets/PackUSPS Global Stamps can be used to mail a 1 oz letter or postcard to any country to which USPS First Class Mail International service is available. They are self stick (peel and stick) for easy mailing. Forever stamps are valid even when the rates go up, so stock up now before the next rate increase. Each stamp has a face value equal to the current Global Stamp rate, so you can use multiple stamps or additional postage to cover your total shipping cost.