The Sovereign's Flag
Here is the flag in the ratio 1:2
The Sovereign uses the Australian Coat of Arms as the base for her own personal Australian flag which is flown, usually as a "Standard" (ratio 22:31), wherever she may be at a particular moment in Australia or when representing Australia abroad.
The crowned "E" set within the seven pointed star used on the national flag brings together both symbols - the Commonwealth and the national flag and the ermine border symbolises the joining together of the States into a Commonwealth. The design of the flag is heraldic.