Related Clues:

• What some lips may be
• Like many passports
• Completely closed
• Closed up tight
• Ready to send
• Securely fastened
• Stamped as authentic
• Fastened as in S.W.A.L.K.
• Leased in secured state
• Secured against leakage
• Closed up, watertight
• Closed tightly, maybe with wax
• Might the dog do the wrong thing in a row?
• Put one's foot down to get the letter ready for the post
• Put the mailed foot down