Further Proving its mastery of chronographs and specifically higher-frequency precision, ZENITH unveils the DEFY El Primero 21 with a new El Primero calibre beating in a phenomenal rate of 50Hz for an exact one/one hundredth of the second chronograph purpose. Motivated by British pilot’s watches from your nineteen seventies, Hamilton’s https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/