Further More proving its mastery of chronographs and specifically large-frequency precision, ZENITH unveils the DEFY El Primero 21 with a new El Primero calibre beating in a phenomenal amount of 50Hz for an accurate one/100th of a next chronograph perform. Now a long time considering the fact that its debut, https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/