The Precision of a Rolex Superlative Chronometer is on the order of −two/+two seconds each day – the speed deviation tolerated through the brand name for a concluded look at is drastically scaled-down than that acknowledged by COSC for Formal certification of your motion by itself. The Superlative Chronometer position https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/