MS-05S Char's Zaku I (MS-05S ザクⅠ（シャア専用機）?) is a mobile suit featured in the Mobile Suit Gundam: The Origin manga, its OVA adaptation and Mobile Suit Discovery . It was Char Aznable's own customized MS-05 Zaku I

Anticipating a war of independence, the Principality of Zeon forces made their preparations for the outbreak of war by mass-producing the MS-05 Zaku I. The MS-05 Zaku I was armed with ranged weapons and a shield affixed to its forearm, and in close combat, it was designed to carry out ramming attacks using the armor attached to its left shoulder. However, a few ideas for revisions were suggested based on mobility test data. A new type of shield mounted on the right shoulder was developed, which could protect the machine over a wider area. And for offense, a new type of left shoulder armor was introduced, with spikes installed for increased damage during ramming attacks. In addition to the standard MS machine gun (drum magazine type) and Type A1 MS bazooka, the MS machine gun (belt-fed type) was developed, which had increased ammunition thanks to a feed mechanism mounted on the mobile suit's back. This new equipment, which eliminated the problems of the MS-05 Zaku I, was intended for use by the improved MS-06 Zaku II that was being developed at a rapid pitch. However, since the war of Zeon independence broke out just before the MS-06 Zaku II entered full-scale mass production, some units of the MS-05 Zaku I were fitted with this MS-06 Zaku II eq