Rolex 3075

History: The Calibre 3075 mechanism was designed for the GMT-Master family of watches. It was built around the architecture of the family’s base movement, the Cal. 3035. It increased the balance speed from the 19,800bph of the Cal. 1575 and introduced the now standard high-beat 28,800bph—the eight ticks per second frequency that gives all Rolexes made since the characteristic smoothly sweeping seconds hand.

Alongside the uprated speed, the 3075 also brought the Quickset date function to the GMT for the first time. A logical improvement for a luxury traveller’s watch, it meant wearers were able to advance the date directly via the crown in its second position, rather than having to wind the center hands through 24 hours. It might seem like a somewhat trivial upgrade, but Rolex’s unassailable reputation has been built on their almost constant striving to improve their customer’s experiences with their products in any way possible, no matter how small.

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