The Precision of a Rolex Superlative Chronometer is of your order of −2/+2 seconds on a daily basis – the speed deviation tolerated because of the manufacturer for the completed watch is noticeably smaller than that accepted by COSC for Formal certification of your movement alone. The Superlative Chronometer standing https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/