Tankissime yellow gold © Cartier
Came out in: 1917.
Particular features: The refined design, Roman numerals with the number four in four vertical lines, sword-shaped hands and sapphire winder.
Louis Cartier was fascinated by tanks circulating the battle fields of the First World War, and went on to create a watch design inspired by the shape of one of these steel monsters seen from above: a square hemmed in by two tracks. He waited until 1919, after the war had ended, before using it to design this now-iconic watch.
There are 40 versions of this watch available today: the Tank Française, the long, rectangular Tank Américaine and the Tank Louis Cartier (with rounded corners). It also exists in platinum, gold, steel or set with diamonds. Certain models pivot so the back of the case can be made visible.