Related Clues:

• Charge option
• Stamp collector?
• Traveler's purchase
• Discover competition
• Credit card offerer
• Type of endorsement
• Shopper's card, often
• International terminal document
• American Express alternative
• Something that's stamped
• Box-office purchase
• See 4 Down
• Border-crossing paper
• Dow 30 company
• Buy one for admittance