The Precision of the Rolex Superlative Chronometer is from the buy of −two/+2 seconds each day – the rate deviation tolerated from the brand name for your concluded enjoy is drastically scaled-down than that recognized by COSC for official certification of the motion on your own. The Superlative Chronometer position https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/