Even More proving its mastery of chronographs and exclusively higher-frequency precision, ZENITH unveils the DEFY El Primero 21 which has a new El Primero calibre beating in a phenomenal price of 50Hz for an correct one/one centesimal of a second chronograph purpose. Equipment Patrol editors selected the Blancpain Air Command https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/