| Heading and notes: | Form number T.G. 56a. COMMONWEALTH OF AUSTRALIA above POSTMASTER-GENERAL'S DEPARTMENT. | 
| Message area: | Blank. | 
| Reverse side: | Blank with a 14 mm strip of adhesive. | 
| Colours (text & form): | Black on light cream. | 
| Size of form overall: | see below. | 
|  | AA-ADG-13B. Used on a Wattle Greetings window envelope (AA-GGE-2) on 27 September 1963. Characteristics: 
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|  Printed in January 1959. | AA-ADG-13C. Used on an INTERNATIONAL OTC window envelope (IAO-EO-5A) on 24 June 1971. Characteristics: 
 
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|  Printed in 1971. | AA-ADG-13D. Used on an INTERNATIONAL OTC window envelope (IAO-EO-5A) on 13 July 1972. Characteristics: 
 | 
Details of use and rarity.
| Form sub-number | Schedule number | Earliest recorded date | Rarity rating | 
| ADG-13A | None | RR | |
| ADG-13B | None | 27 September 1963. | RR | 
| ADG-13C | O/N.C.2065. - 1/59 | 24 June 1971. | RR | 
| ADG-13D | QTN. C. 810/71 | 13 July 1972. | RR |