The Date Window

Yes, the date window is technically a watch complication. The most famous implementation of this humble (yet supremely useful) feature is perhaps the perfect replica Rolex Datejust watches. Launched in 1945, it was named for the precision with which the date flips over exactly at midnight. Still produced 70 years later, the Datejust is said to be the Crown’s best-selling model. (An interesting tidbit: According to market data, watches with date functions far outsell those without them.)

The Day-Date

Once again, best fake Rolex watches were present at the beginning of the revolution in a particular complication, this time with the day-date display. In 1956, for the first time, it displayed both the date and the day in an arc at 12 o’clock. Many other high quality copy watches (such as those powered by the famed Valjoux 7750 movement) display them sequentially one after the other; IWC replaced this movement more recently with its own in-house calibers boasting the same functionality.

The GMT

The GMT watch was — yet again! — a Rolex invention. In 1955, the Crown debuted a design made for Pan American Airways pilots that allowed for the simultaneous display of both a local time zone and an additional time zone. Achieved via the use of a fourth hand and a rotating 24-hour bezel, it’s still best encapsulated by the cheap super clone Rolex GMT-Master II watches, although myriad other marques also make GMT models.