The minimum height for the Navimow Terranox to pass through a passage, fence, or small gate should be at least 40cm (15.75"), and the minimum width should be 100cm (39.31"). These dimensions ensure that the Navimow Terranox can navigate comfortably without obstruction. If the passage is too narrow or the height is insufficient, the Navimow Terranox may have difficulty passing through or may get stuck.