In order to publicize the Postal Zone Number as well as to appeal to mail users for supporting its Postal Zone Code which was introduced on March 20, 1970, by the Postal Administration of the Republic of China, a set of stamps was issued. Consisting of three digits, indicating place of delivery and delivery zone or office, written in a box is the upper right corner of the envelope, the Chinese Postal Code numbers can be recognized by the automatic sorting machine and items thus properly sorted. The 1.00 stamp features the Postal Zone map of Taiwan, while the 2.50 stamp depicts the Chinese Postal Zone emblem-a standard envelop carried by a bird, which is the faithul and loyal messenger in Chinese mythology.