Patek Philippe�s long-standing complication is sometimes called "dual time zone" or "travel time" by the brand, and a second hour hand is added to the dial to show the time in another time zone. The added hands are usually presented in a different way from the local hour hand, and can be hidden under the local hour hand when not in use, and Patek Philippe has installed a pair of buttons on the side of the left case to move forward or backward the extra hour hand. chronosale.co