The Precision of a Rolex Superlative Chronometer is in the purchase of −two/+two seconds daily – the speed deviation tolerated from the brand to get a completed view is considerably scaled-down than that recognized by COSC for Formal certification on the movement by yourself. The Superlative Chronometer status is symbolized https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/