Related Clues:
- Bus. letter attachment
- Collier's work: Abbr.
- Ltr. accompanier
- Ref. set
- Abbr. spotted in the mailroom
- 5 Placed inside: abbr.
- Cover sheet abbr.
- Envelope or memo abbr., perhaps
- Mailroom abbr.
- Abbr. often before a name
- Ltr.-routing word
- SASE, for example
- What's inside an env.
- Business-envelope abbreviation
- Ltr. directive