The MS-06S Zaku II Commander Type looks very similar to the standard MS-06F Zaku II, so much so, that the Earth Federation can generally only tell the difference from color schemes most pilots apply to their units and the increased performance of this version. It first appears in the anime series Mobile Suit Gundam.. Click the gundam wiki logo image on the right for more information.
The S-Type Zaku II features a squad-leader "antenna" that is mounted on the head on the Zaku II for enhanced communication capabilities, which is used to designate squad-leaders or higher ranking pilots from other squad-members or lower ranking pilots. It also featured a more powerful powerplant, which in turn, gave the S-Type Zaku II greater thrust and acceleration. However, since no changes were made to the fuel tanks, the S-Type's operating time is shortened as a result. This allowed them to move at speeds 3x faster than a normal Zaku II (This figure was later retconned to +30%). This made it incredibly dangerous in the hands of the ace pilots it was handed out to, such as the "Red Comet" Char Aznable, who sank 5 Magellan-Class Battleships in the Battle of Loum.