Related Clues:
- Second afterthought, for short
- Letter ender?
- In an env.
- Later afterthought: Abbr.
- Second addendum to a letter, briefly
- Letters before a second afterthought
- Bus. letter extra
- SASE, perhaps
- Business letter abbreviation
- Letter addition letters
- Envelope contents: Abbr.
- Second letter afterthought
- Env. insertion
- Second ltr. addenda
- Second addition to a ltr.