Related Clues:
- Something you get Saturday, but not Sunday
- Armor
- Knightly wear
- Knights' garb
- 'You've Got --'
- Send, as a postcard
- Bus. letter attachment
- It might be registered
- Check inside?: Abbr.
- It may be express
- SASE, for example
- Placed inside a pkg., e.g.
- Abbr. on a business letter, perhaps
- Postmarked pieces
- Push the envelope?