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Dual time watches are equipped with two hour hands to indicate two different time zones. The primary hour hand must be independently adjustable by hour increments, and the second-hour hand indicates 12 or 24 hours. They are more complicated than a GMT because they move on two subdials, however, both serve the same purpose.
The difference between a dual time watch and a GMT watch is usually the scale. A dual time watch has a 12-hour scale, while a GMT watch has a 24-hour scale. Most dual time watches have a day/night indicator, and a hand that can be adjusted more easily than a GMT watch.
