Seiko 7B24 Manual - Page 29

Time Zone Adjustment Function There are time differences around the world based on "Coordinated Universal Time (UTC)." There are 24 regions (Time Zones) around the world with a time difference of one hour. This system has been adopted internationally by setting the total time difference around the world as 24 hours. In addition, Daylight Saving Time (Summer Time) is individually adopted in some regions. [What is UTC (Coordinated Universal Time)?] U TC is the universal standard time coordinated through international agreement. It is used as the official time around the world. UTC is determined by adding a leap second to GMT (Greenwich Mean Time), which is determined through astronomical measurement, in order to keep the precise time. [What is summer time (DST)?] S ummer time is daylight saving time. Advancing the watch one hour to prolong daytime during longer daylight hours in summer. Daylight saving time has been adopted in about 80 countries, mainly in Europe and North America. The adoption and duration of daylight saving time vary depending on the country. ※ Time differences between regions and daylight saving time may change due to circumstances of a country or region. ※ A time difference established in 15 minute or 30 minute units is adopted in very limited regions (ex. India). 109