The Precision of a Rolex Superlative Chronometer is with the buy of −2/+two seconds on a daily basis – the rate deviation tolerated from the brand name for a concluded view is noticeably scaled-down than that acknowledged by COSC for official certification of your movement by itself. The Superlative Chronometer https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/