One key requirement of alarm watches is to have what?

For an alarm watch, one essential feature is the presence of a second crown or pusher. This additional control provides the functionality needed to set the alarm independently of the main timekeeping functions. A second crown or pusher allows easy adjustment and activation of the alarm without interfering with the primary time display, which is particularly important for users who need the alarm function to be both reliable and user-friendly.

Having a third hand is not a requirement for all alarm watches; in fact, many alarm watches can operate effectively with just the standard hour and minute hands. A digital display, while helpful in some alarm watches, is not a prerequisite, as many analog models incorporate alarms without a digital interface. Additionally, a special battery is not a distinct requirement for alarm watches; they can function with regular batteries, provided they are compatible with the watch’s features. Thus, the second crown or pusher stands out as the critical requirement that facilitates the unique functionality of alarm timing.