Related Clues:
- Mail aid
- The White House's is 20500
- Kind of bolt
- Go with haste
- Five-digit postal number, informally
- ___ + 4
- Do (up), as a fly
- Number after many a state postal abbr.
- Sleeping bag closure
- USPS acronym
- Flip back and forth, as an on-off switch
- It may be under a fly
- Close, as a parka
- Nothing ... or a hint to what's hidden in 20-, 35- and 52-Across
- Fastening device for boy scout's kerchief