Duyun 1 16 is located at the foot of Mangshan Mountain in duyun city. It used to be the location of South China Instrument Factory (factory 454 1, mailbox 1 16). Established in 1965, Nanhua Instrument Factory is one of the important enterprises designated by the Ministry of Machinery Industry to produce military optical instruments and civil optical instruments. Duyun 1 16 used to undertake the production tasks of this factory, which became one of the symbols of this factory, representing the location and related historical background of this factory.