what permission and licenses are required for making wrist watches ?

Wrist watches are like any other product but they are important as they have a very important work to do i.e. to show us time. Watches are the one on whom we rely totally so they are supposed to be accurate and not at all misleading.So,wristwatch manufacturers should be careful about the correction of time. Correction of time varies with the type of mechanism used in the watch.If the watch is mechanically designed to align itself to Standard Time then there is no danger to loose  in view the special and crucial feature of watches,there may be various permissions and licensing that have to be done before starting the manufacturing of wristwatches.