| Clue | Source | Date |
|---|---|---|
| Small green sign on a highway | ||
| *Numbered highway sign | Universal | 01 Jul 2022 |
| *Roadside assistance, of a sort | Wall Street Journal | 15 May 2019 |
| *Roadside assistance, of a sort | ||
| Sign of note for a stranded motorist | The Washington Post | 20 Nov 2016 |
| Numbered highway post |