Announced in 1988 at the Basel spring fair, the Rolex Daytona 16520 marks an important change in the history of the chronograph. Discontinuing the manual Valjoux 727 movement, Rolex decided to use a highly modified Zenith El Primero automatic movement renamed Caliber 4030.
Besides offering a new movement and design, the wristwatch was crafted with a sapphire glass, had a larger case and appeared with a white dial with subsidiary registers framed by black chapter rings, such as the present wristwatch, or a black dial with subsidiary registers framed by white chapter rings.
Reference 16520 became an instant success throughout the globe and commanded important waiting lists. With production of the reference officially stopping in 2000, the chronograph is still highly sought after by enthusiasts of the brand.