4161

The Yacht-Master II utilizes calibre 4161, a self-winding mechanical regatta chronograph movement designed and produced exclusively by Rolex. Following more than 35,000 hours of engineering, the Yacht-Master II debuts a regatta countdown featuring a distinct, patented mechanical memory developed by Rolex. Several of the 4161's 360 components are so intricate or minute that they require advanced, state-of-the-art technology for production. Similar to the Sky-Dweller, the Yacht-Master II incorporates a 'Ring Command' bezel that functions with the movement to serve as the interface for the programmable countdown. As with every Rolex Perpetual movement, the 4161 is a certified Swiss chronometer, a title granted to high-precision timepieces that have cleared the Swiss Official Chronometer Testing Institute (COSC) examinations. Its structure, shared by all Oyster watch movements, ensures exceptional reliability. Chronograph: Chronograph, Column wheel, Countdown. Additionals: Chronometer