The movement of a balance from one extreme to the other. In a classic watch movement the balance oscillates at a speed of 5 vibrations/second or 18,000 vibrations/hour. In modern watches the number of vibrations has been increased to 19,800, 21,600, 28,800 and 36,000. TAG Heuer holds the record for the highest frequency in a mechanical wrist watch with the Calibre 360, which makes 360,000 vibrations/hour.