The second U.S. stamp to feature an automobile, the 1925 Special Delivery stamp depicted a post office delivery truck. The electric auto had been the subject of the 6-cent Pan American Exposition Issue twenty-five years earlier. In this newest Special Delivery issue, the operations side of the post office was on display. Where earlier issues had focused on the messenger, this stamp illustrated the loading of the truck with packages and mail taken directly from the post office building.
The twenty-cent 1925 Issue had been machined with size 11 perforations and accommodated the higher rates of Special Delivery and Parcel Post services combination mail. The 1951 20-cent Post Office Truck would be issued with size 11x10.5 perforations.