Issued on July 4, 1939, this commemorative series from the Republic of China celebrates the 150th anniversary of the founding of the United States and highlights the diplomatic relationship between the two nations. The set of four stamps, ranging in denomination from 5 cents to 1 dollar, was printed by the American Bank Note Company using multicolor gravure and features detailed imagery of flags, maps, and symbols of unity. Each stamp measures 55 x 40 mm and is perforated 12. Valid until March 31, 1940, these stamps reflect a key period of international cooperation in the years leading up to World War II. This example bears a well-struck circular cancel from Yunnanfui, a location of historical interest and postal significance. Cataloged as Michel CN-IM 308–311, Scott CN-IM 364–367, Yvert et Tellier CN-IM 289–292, Stanley Gibbons CN-IM 501–504, and China Stamp Society CN-IM 425–428. Condition Fine used with clear postmark and strong design impression. Estimate "$70 – 90"