Related Clues:
- Interoffice mail abbr
- Letter's "To:" line: Abbr
- Abbr. at the top of a 111-Down
- Memo routing abbr
- Routing letters on an envelope
- This is for, for short
- Letters on an envelope
- Abbr. at the top of an office memo
- Letter opener: Abbr
- Directive on an env
- Sent-along email abbr
- Email abbr
- Not backward, abbr
- Ahead, abbr
- Fax cover page abbr