There are two variations of the Panama-Pacific Exposition Issue's 2-cent stamp. The first, released in 1913, has perforations 12. The second, issued in 1914, has perforations 10. The Pedro Miguel Locks appear in the stamp's vignette. Construction on these locks was completed in 1911, two years before the Panama-Pacific Exposition opened.
The 2-cent stamp most often paid the two-cent first class domestic rate. It was also commonly used with other denominations to fulfill large weight and foreign destination rates. An estimated 500 million of these 2-cent stamps were printed by the Bureau of Engraving and Printing and issued to the public.