| Heading and notes: | Form number E.T. No. 55. Standard Imterim heading. | 
| Message area: | Seven lines. | 
| Reverse side: | Blank. | 
| Colours (text & form): | Black on green. | 
| Size of form overall: | 134 × 194 mm (top section only) | 
| Size of datestamp box: | 23 × 30 mm. | 
|  | WI-RO-1. Ravensthorpe to Perth 
 | 
Details of use and rarity.
| Form sub-number | Schedule number | Earliest recorded date | Rarity rating | 
| DO-1 | None on this section. | 12 February 1910 at Perth ETO. | NC |