In 1988, the Daytona turned 25 years old. Rolex decided to celebrate the occasion with a model which immediately captivated the attention of the public. The first self-winding chronograph model in the history of the company was introduced, the landmark reference 16520. The model is powered by a derivative of Zenith's El Primero calibre, substantially modified by Rolex. It was the first Daytona to be equipped with a sapphire crystal and a new larger diameter of 39mm.

The launch of the reference 16520 was an immediate success, resulting in unprecedented demand which translated into years-long waiting lists for clients. Without a doubt, the reference 16520 elevated the Daytona to its current mythical status.

This example is part of the famous 'R' series from the first year of production in 1988. As expected, the watch is fitted with the highly sought-after black glossy dial featuring the floating "Cosmograph" signature and it also retains its original calibrated bezel graduated to 200 units per hour. The floating dial presents a very unusual graphic layout with the Cosmograph designation markedly separated from the other four lines of text. Not only are its aesthetics striking, but it furthermore represents the link between four-line and five-line dials.