Further More proving its mastery of chronographs and exclusively large-frequency precision, ZENITH unveils the DEFY El Primero 21 which has a new El Primero calibre beating at a phenomenal level of 50Hz for an accurate one/one hundredth of the second chronograph perform. The phrase “chronometer” took on a slightly broader https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/