Even More proving its mastery of chronographs and specifically superior-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 1/one hundredth of the next chronograph perform. Now a long time because its debut, TAG has https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/