The DF-15 (CSS-6) , better known by the export name M-9, is a sophisticated solid-fueled, single-stage mobile missile, similar in appearance to the US Pershing I-A system. The M-series missiles all use solid fuel, and operational preparation time is short. The DF-15 is expected to be equipped with a variety of warhead types and to become the mainstay of China's sub-strategic missile force.