Cartier's "Santos" is a historic collection that began sales in 1911 and continues to be Cartier's flagship model to this day. This watch combines elegance with a sporty feel, with a rounded square case, screw-fastened bezel and bracelet, and Roman dial. A wide variety of variations are available, and Ladies and men's lines are popular. The Santos is said to have been developed by Cartier in response to the requests of aviator Alberto Santos Dumont, and is said to be the world's first wristwatch to use a case and lugs specifically designed for wristwatches.

The Santos Dumont is a derivative of Cartier's Santos series, which was launched in 1911. Compared to the original Santos model, it features a thinner case, a more linear design, and a more subtle screw fastening design. It features a design suitable for formal occasions and the sophisticated details of a dress watch, making it the perfect model for those who appreciate elegant style.

The Santos Galbe is part of Cartier's Santos collection and is known for its curvaceous design. The curved case improves wearing comfort and has a different appeal than the angular design of the original Santos. Skeleton dial variations are also available, allowing you to enjoy innovative designs. This Unisex model has gained support from a wide range of people, regardless of gender.

Santos 100 is a commemorative model of the Santos collection released in 2004. It features a thick, sturdy design that incorporates the trends of the time, making it suitable for those who prefer a bold, contemporary style.

Santos Demoiselle is part of the Santos collection for Ladies and features a slender bracelet and small case. It maintains the classic Santos design elements while adding a more sophisticated and feminine touch.

Cartier's Tank collection has been one of Cartier's most popular and well-known watch collections since it began selling to the public in 1919. The design was inspired by the tank ruts of World War I, reflecting the flat top shape of tanks from that era. More than 100 years later, it remains one of Cartier's most iconic collections.

There are several different models of tanks. Examples include ``Tank Louis Cartier,'' ``Tank Française,'' ``Tank American,'' and ``Tank Anglaise.'' Each has its own unique characteristics, but all share the basic design elements of a tank.

"Tank Louis Cartier" is a Cartier watch collection created in 1922 and named after Louis Cartier, the founder of the Tank series. This model is also known to have been worn by Louis Cartier himself, the grandson of Cartier's founder. Crafted from precious metals such as 18K gold, pink gold, and yellow gold, and featuring a sapphire-set crown, this collection is one of the most prestigious of the Tank series, and is positioned as part of the brand's prestige line.

``Tank Solo'' is a collection derived from Cartier's iconic ``Tank'' series and was launched in 2004. This year marks the 100th anniversary of the world's first wristwatch, the Santos, manufactured by Cartier. The Tank Solo features a particularly modern design among the Tank series, and was popular as an entry model at a relatively reasonable price. However, production ended in 2021 and it is currently only available on Used market. Tank Solo is designed with a modern interpretation while inheriting the philosophy of "Tank Louis Cartier", and is popular among the Tank series due to its simple and gender-neutral design.

Cartier's Tank MC is part of the men's collection and is named after the initials of Manufacture Cartier. Equipped with the in-house Automatic winding movement "Caliber 1904 MC", it has a 48-hour power reserve and the movement can be viewed from the back of the skeleton structure. It features a strong and masculine design, and the case size of 44mm x 34.3mm is stylish and easy to match with a wide range of fashion styles. Although it is a relatively new line in the Tank series, it has grown to become Cartier's new standard as a popular model of men's watches.

The "Tank Mast" is part of Cartier's Tank series, and the "Must" in the name means "something you must have" and is a historic model that has transformed Cartier into a brand loved by many. The case, which is decorated with the special "Vermeil" technique, is a dress watch that is suitable for everyday use, with a high brilliance at a reasonable price. Introduced in the 1970s, the Tank Must, with its elegant design and affordable price, helped increase Cartier's popularity. Although it is no longer in production, it has gained a strong following.

"Tank Anglaise" is a new collection added to Cartier's popular "Tank" series in 2012. This model features a unique design with the crown buried in the case and a rectangular shape typical of the Tank series. They come in a wide range of sizes, from elegant models decorated with diamonds to practical stainless steel models, and their Unisex designs are popular with both men and women. However, production ended in 2019, and it is currently a difficult model to obtain. "Anglaise" means "English style" in French, and was born as a homage to London, England. A masterpiece that combines sporty atmosphere and elegance, and is a collection that symbolizes Cartier's history.

Cartier's "Pasha" collection is a sporty and elegant watch that is highly popular among men. This collection has its origins in the Tank Etanche, which was manufactured in response to the requests of the Moroccan nawab in the 1930s, and was revived in 1985 as the highly waterproof Pasha collection. It features a distinctive round case, crown protector, and dial with excellent visibility. In 2020, the men's line has been revived, attracting new attention with changes to the crown design and adoption of the "Quick Switch" system. In addition, there are many derivative models such as the Miss Pasha, Pasha C, and Pasha 42, and the sporty yet elegant design matches a wide range of styles and is positioned as part of Cartier's innovative design.

Pasha C is a model from Cartier's Pasha collection that features a particularly casual and youthful design. Although it has a sporty element, it retains the elegance of Cartier. It features a compact case size and a simple dial design, making it suitable for everyday use.

Miss Pasha is a model from the Pasha collection, which is specially designed for Ladies. Featuring a small case size and sophisticated design, this is an elegant watch that looks beautiful on a woman's wrist. It also includes decorative elements such as jewelry, making it attractive as a fashion accessory.

The Pasha 42 is a model that features a larger case size and a design that gives a masculine impression. The 42mm case has a strong presence and is suitable for those who prefer a bolder style. The sporty yet sophisticated design is suitable for a wide range of occasions, from casual to business occasions.

"Ballon Bleu de Cartier" is a collection released by Cartier in 2007 that means "blue balloon" in French. Unlike the rectangular and linear "Tank" series, it features a rounded design and has been established as a new Cartier standard. Ballon Bleu is characterized by its dome-shaped Crystal, blue cabochon crown, and round case, giving it an elegant and cute look. Available in quartz and Automatic winding movements, and in a variety of materials and sizes, they are popular among a wide range of people, both men and women.

"Calibre Cartier" is a collection exclusively for men released by Cartier in 2010, and is characterized by its powerful design. Unlike the traditional image of Cartier's elegance, it gained popularity for its masculine appearance. The collection includes basic models, models with chronographs, and diver's watches that are water resistant to 300 meters. It is equipped with the 1904PS MC Automatic winding movement designed and manufactured in-house by Cartier, demonstrating Cartier's status as a manufacturer. Although production ended in 2020, its charm is still highly praised.

Cartier's ``Roadster'' was released in 2002, and was a sports line wristwatch for men, followed by the ``Roadster Mini'' for women. Inspired by sports cars from the 1950s and 1960s, this model features a design that combines Cartier's signature elegance and sportiness. Although it is out of print, it is still popular. Of particular note is the revolutionary one-touch exchange system, which allows straps to be changed by simply pressing a lever, a feature later adopted by many other watch brands.