Starting with the MS-01, which was announced by the Principality of Zeon as a special heavy fighter for outer space, it was deployed as a multifunctional heavy fighter weapon for the start of the war against the Earth Federation Forces. General-purpose heavy fighter. As a further refined weapon of MS-05 (commonly known as Zaku), which had reached the stage of almost completion as a tactical weapon, it brought about the result of showing off its overwhelming strength starting with the first battle of Ruum. The degree of perfection of the design is extremely high, and it is a masterpiece that has produced various variants corresponding to the operational style and was used throughout the war as a development bed for local warfare aircraft according to the application. The total number of production machines with the same machine number is 8,168.