Rolex 1530

History: Rolex originally launched the Calibre 1530 as a 17-jewel movement. It went through a number of significant upgrades itself during its successful run before retiring in 1965. They also released it in 25 and 26 jewel versions. Its initial butterfly rotor graduated to the familiar half-moon type. Also, they replaced the brass colored gears with the red, Teflon-coated variety we generally see today.

While extremely precise and reliable, Rolex considered the Caliber 1530 very much a workhorse caliber. Therefore very few were submitted for chronometer certification. Instead, Rolex fitted the movement into several of their non-chronometer models, such as the Air-King and the earliest versions of the Submariner, watches they initially deemed not to need mechanisms that had passed the rigorous COSC tests.

However, ask any watchmaker today what in their opinion is the best movement Rolex ever produced, and many will still say the Cal. 1530. Its lack of certification was down to its relative difficulty in regulating consistently rather than its overall accuracy. Before the innovation of Microstella screws were first introduced in 1959 on the Cal. 1565, the previous screw balance was far trickier to adjust, especially considering the volume of movements Rolex produce.

Features List: Self-winding movement, bi-directional winding; Breguet hairspring; Escapement: Stone lever; Yoke winding system; Screwed balance; Shock protection KIF Flector.

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