This Zanti Prison Ship is a spacecraft that was created to bring the most dangerous criminals (or misfits) of the alien planet Zanti to Earth to keep them from further threatening their people.
The Zanti sent this ship to Earth, specifically because they are, as a species, incapable of executing their own and they know humans are "practiced executioners".
The prisoners were watched over by guards of the same violent persuasion as the prisoners themselves.
Its full capabilities, if any, are unknown, but it is sufficient enough to cross from planet Zanti to Earth.
It is shown to move in three dimension while in Earth's atmosphere.
It held inside itself an excess of one-hundred Zanti.