V for victory; submarine mail through the Panama Canal via USS C-3
| Image2 | |
| City | Cristobal, Canal Zone |
| State | |
| Subject | Postal |
| Description | V for victory; submarine mail through the Panama Canal via USS C-3 |
| Year | 1919 |
| Month | 5 |
| Day | 7 |
| Color | black |
| Notes |