Cartier's design inspiration was the world's first armored tank, which debuted in 1916; the casing around the watch's face like this W51007Q4 has mimicked the look of the machine ever since. This "Francaise" version is set with an octagonal crown set with a faceted spinel, sword-shaped hands, 18K gold and stainless steel case and bracelet, and is water resistant to 100 feet.