| Heading and notes: | Form number E.T. No. 1a. Special space at right under date stamp for recording sending details. |
| Message area: | 30 boxes in six lines. |
| Reverse side: | Blank. |
| Colours (text & form): | Black on dull orange brown. |
| Size of form overall: | 127 × 202 mm. |
| Size of datestamp box: | 22.5 × 31 mm. |
Details of use and rarity.
| Form sub-number |
Schedule number | Earliest recorded date | Rarity rating |
| 1A | B. 875/12.17. - C16686. | RR | |
| B. 875/12.17. - C16686. - 100M. | |||
| 1B | None. | RRR |