Related Clues:

• Letter attachment
• Feature of a certain album
• Album item
• Philatelist's concern
• Piece of postage
• Inverted Jenny is a rare one
• PAID, for one
• Characteristic mark
• It's usually stuck in a corner
• Snail-mail need
• Licked square
• Envelope stick-on
• Perforation site
• Mailing need
• If it's canceled, it's accepted