More Proving its mastery of chronographs and specially large-frequency precision, ZENITH unveils the DEFY El Primero 21 that has a new El Primero calibre beating at a phenomenal fee of 50Hz for an exact one/100th of a next chronograph perform. 1844: Adolphe Nicole introduces the reset attribute, allowing for distinctive https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/