Chen-2 bottom mine

The Sinking-2 (Chinese: 沉-2, Transliteration: Chen-2) bottom mine was the first indigenous designed Chinese naval mine that could adopt a range of fuzes, such as acoustic, contact, infrasonic, ultrasonic and magnetic fuzes. The project was jointly developed by Fengxi Machinery Factory (Chinese: 汾西机器厂) and the 710th Research Institute in 1972, and was mainly used for coastal regions. The mine was accepted into service in 1975.