This orange stamp, the third stamp issued in the 1938 Presidential Series is an anomaly: 1) It pictures Benjamin Franklin who was never a President of the United States, and 2) No rate ever existed that would have been paid solely with this half cent stamp.
Benjamin Franklin (1706-1790) does have a major connection to philately. Among his many achievements, Franklin served as the first Postmaster General of the United States. For that, and for all his other achievements, he was honored when his picture was engraved on the first postage stamp to be issued by the United States in 1847. His likeness has grace many postage stamps issued by the United States, and other countries ever since.
It is fitting that Benjamin Franklin be included in the 1938 Presidential Series. Many scholars agree that if it wasn't for Franklin's advanced age at the time of the creation of the United States, he would have surely been elected President.
Millions of these Franklin stamps were used to pay postal rates, but no single rate ever existed for the half cent Franklin. A collector wanting to show a single franking on cover would have to resort to showing this half cent stamp affixed to a stamped envelope, postal card, or an envelope with a meter.
The likeness of Franklin on this stamp was taken from a photograph of a statue by James Earl Fraser which stands in the Franklin Institute, in Philadelphia, PA, where the stamp was first put on sale on May 19, 1938.