The Ten-cent Prexie
The domestic air mail rate was five cents from October 1, 1946 to January 1, 1949.
This double-weight free-frank official envelope was sent airmail, so it required regular postage. Double the rate in 1947 would have been ten cents.
The rate to Canada was the same as domestic during the five-cent airmail rate period. This double-weight cover was sent airmail from an APO address in Austria to Canada in 1948.