Rolex 3135

History: The 3135 is a continuation of the 3035 series. Rolex launched it in 1977 and was profoundly different from its predecessors. As the company’s first high-beat movement, it increased the balance speed from 19,800 BPH to 28,800 BPH. This higher frequency has since become the standard across all of Rolex’s range. It also allowed the caliber to provide more accurate timekeeping and better withstand outside influences, such as shock. Like most Rolex mechanisms ending with a "5", this unit has a date function. All modern Rolex date-equipped mechanisms have a 'Quickset' feature as well.

The popular caliber 3135 measures 28.50 mm in diameter and 6.00 mm in height. The Submariner uses this caliber. This makes it quite large when compared with other Rolex movements. The larger size of the movement means that it is more robust and has the ability to incorporate more parts and components. This allows the watch that utilizes it to perform more reliably and durably. It also offers a frequency of 28.800 vph.

Manufacturer: Rolex SA (/ˈroʊlɛks/) is a Swiss luxury watchmaker. The company and its subsidiary Montres Tudor SA design, manufacture, distribute and service wristwatches sold under the Rolex and Tudor brands. Founded by Hans Wilsdorf and Alfred Davis in London, England in 1905 as Wilsdorf and Davis, Rolex moved its base of operations to Geneva, Switzerland in 1919. Forbes ranked Rolex 64th on its 2016 list of the world's most powerful global brands.[Rolex is the largest single high end watch brand. The company is owned by the Hans Wilsdorf Foundation, a private family trust.

Alfred Davis and his brother-in-law Hans Wilsdorf founded Wilsdorf and Davis, the company that would eventually become Rolex SA, in London, England in 1905. Wilsdorf and Davis' main commercial activity at the time involved importing Hermann Aegler's Swiss movements to England and placing them in high-quality watch cases made by Dennison and others. These early wristwatches were sold to jewellers, who then put their own names on the dial. The earliest watches from Wilsdorf and Davis were usually hallmarked "W&D" inside the caseback.

From Wikipedia