The SS4 (Chinese: 韶山4) is a kind of AC-powered electric locomotive used in China. It was built by Zhuzhou Electric Locomotive Works in 1985 and is still produced as of 2010. It also has an updated version: SS4G (Chinese: 韶山4G/韶山4改').
SS4 0110 at Longhai Railway, near Xi'an
SS4 at Yangpingguan
SS4G 1015 in Luopoling, Beijing