This 1947 commemorative series marks the 50th anniversary of the Chinese Post Office, featuring a vibrant quartet of engraved designs printed by the American Bank Note Company. The set includes denominations from 100 to 500 Chinese dollars, each highlighting different modes of transportation and postal progress. The 100$ purple design shows maritime and rail transport symbolizing early global connectivity; the 400$ red and 500$ blue stamps each display traditional Chinese junks alongside modern aircraft; while the 20000$ green and 30000$ brown stamps (also associated with this set though listed separately) feature a postal courier trekking through rugged terrain, escorted by a mail truck. The stamps were printed by gravure with line perforation 12, and all are ungummed as issued. They commemorate the transformation of China’s communications infrastructure from 1896 to 1946, during a period of political upheaval and modernization. Cataloged as Scott IM777–780, Michel CN-IM 831–834, Yvert CN-IM 597–600, Stanley Gibbons CN-IM 986–989, and China Stamp Society CN-IM 1182–1185. This mint never hinged group is well preserved, with vibrant color and excellent centering throughout. Estimate "$140 – 170"