The Precision of a Rolex Superlative Chronometer is from the order of −2/+2 seconds per day – the speed deviation tolerated by the manufacturer for your completed view is drastically scaled-down than that acknowledged by COSC for official certification in the movement by yourself. The Superlative Chronometer standing is symbolized https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/