 The Shanghai III-class gunboat is more heavily armed than its predecessor, with the 23 mm guns replacing the 14.5 mm heavy machine guns and is also substantially larger at 170 tons.Significantly more Shanghai III-class gunboats have entered service in foreign navies than in the People's Liberation Army Navy, and the ones in the Chinese inventory are mainly used for training foreign crews, and not all export boats have the same configuration due to different customers' requirements.They are primarily used for coastal and inland patrol.