Variable value stamp

A variable value stamp is a gummed or self-adhesive postage stamp of a common design, issued by a machine similar to an automatic teller machine (ATM), with a value of the user's choice printed at the time the stamp is dispensed. The value may be variable or from a fixed selection of postal rates. The stamps and machines are typically for use in retail or post office environments. As only the postal value varies from stamp to stamp, these stamps have been described as key type stamps. They are also closely related to meter stamps from postage meters.

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