The Twenty-one-cent Prexie
Airmail special delivery use
The special delivery fee was thirteen cents and the airmail rate was eight cents per ounce from November 1, 1944 until October 1, 1946.
This cover was sent airmail special delivery from Massachusetts to Missouri in June of 1946 for twenty-one cents.
The airmail rate was six cents per half ounce and the special delivery fee was fifteen cents from January 1, 1949 until January 1, 1952.