Even Further proving its mastery of chronographs and especially higher-frequency precision, ZENITH unveils the DEFY El Primero 21 having a new El Primero calibre beating at a phenomenal charge of 50Hz for an accurate one/one hundredth of the 2nd chronograph purpose. Declaring the winner on the race to build the https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/