Related Clues:

• The 'F' and 'B' of Samuel F. B. Morse, e.g.: Abbr
• DDE and JFK, e.g
• P.O. stack
• Monogram units: Abbr
• D.D.E. or J.F.K
• 19-Down, e.g.: Abbr
• Brief missives?
• A and P, e.g.: Abbr
• Fillers of envs
• OK components
• Monogram, e.g.: Abbr
• Approval indication: Abbr
• JFK, e.g.: Abbr
• Mail: Abbr
• Quick signature: Abbr