First introduced in 1945, DateJust was the first watch not only to display the date automatically - and have it verified by an official chronometer certificate -- but to move the numbers to the next day's date at precisely 12:00 AM. 

It was also the world's first fully waterproof men's watch with automatic winding and central seconds-hand. 

The Rolex Datejust is the front runner of the Rolex Oyster Collection. It is available in a broad range of styles.