Tank and Santos are both long-established watch collections from Cartier. They share common features such as square cases, Roman numeral hour markers, and blued steel hands (on some models) https://www.aomwatches.is/.
The Santos predates the Tank. According to the brand, the series was created in 1904, and the name "Santos" is directly derived from the aviator Alberto Santos Dumont. His friend Louis Cartier designed a wristwatch suitable for flight, which became the prototype for the series. Based on this, it is considered one of the world's earliest men's wristwatches. The Tank series, on the other hand, was created slightly later, with the prototype appearing in 1917 during World War I. As its name suggests, its design was inspired by a top-down view of a Reynolds tank from World War I, with the lugs seamlessly integrated into the case.
The Tank series is simple and understated, with watches leaning more towards a dress style; while the Santos series, with its pilot's watch heritage, leans more towards a sporty and industrial style. Over time, both have developed into large product families, offering various materials and complex functions. For a clearer comparison, the following refers to their respective "standard models," or entry-level versions.
Before the "quartz revolution," Cartier Tank watches mostly used precious metal cases, naturally resulting in high prices. To better integrate with contemporary trends, the Tank Must series was born. While maintaining the basic design, the historical Tank Must replaced the movement with a quartz movement, and the case material changed from pure 18k gold to silver with a gold-plated finish, the so-called "gold-plated silver." These changes further lowered the price, creating an opportunity for more enthusiasts to experience Tank watches.
