Marine Hi-Zack was the amphibious type of
Zaku II that produced by Principality of
Zeon. They served in the submarine squadron, Sea Serpent, at North
Atlantic Ocean during the One Year War and tested as waterproofed Mobile
Suits. After the One Year War, they were forfeited by Earth Federation
and started to serve in the military intelligence department. They were
used for coast defence and blockade in some coastal military areas.
After Earth Federation received them, Marine Hi-Zack were repainted
the color from green to sea blue and the model number of some units
changed to MSM-01. In Zeta Gundam, Marine Hi-Zack was used for sea
defence when Titans negotiated with Karaba in new Hong Kong City.
It was the only amphibious Mobile Suit that appeared in Zeta Gundam series.