It was a tribute to the Allied Troops and their tanks. Hence, the name and the form. The model started in 1917 but made public in 1919 once the peace had returned. Tank watches are easily recognizable because of their crossbars, sidepieces and their rectangular or square form. It belongs to the most important watches in history and it is one of the pillars of Cartier. No wonder that, for example Andy Warhol, Jackie Kennedy, Yves Saint Laurent, Frank Sinatra and Calvin Klein, all wore one.