China Telecom Guangdong Provincial Branch joined hands with Hong Kong Telecom in publishing two sets of phone credit cards featuring China's scientific progress throughout Chinese history.

Guangdong's phone credit cards feature block printing, man- made satellites, the scientific treatise "Tiangong Kaiwu" by the Ming dynasty scientist Song Yingxing (1587-?) and the Forbidden City.

The Hong Kong phone credit cards feature cards reflecting the application of firearms, Compendium of Materia Medica by Li Shizhen (1518-1593), the abacus and the voyage of the maritime explorer Zheng He (1371-1435).

The credit phone will enable users to make local, country and overseas calls.