Rolex caliber 2231

Calibre 2231 is a self-winding mechanical movement entirely developed and manufactured by Rolex. Like all Rolex Perpetual movements, the 2231 is a certified Swiss chronometer, a designation reserved for high-precision watches that have successfully passed the Swiss Official Chronometer Testing Institute (COSC) tests. Its architecture, in common with all Oyster watch movements, makes it singularly reliabl