Rolex thrilled the public at the 1988 Basel Fair by introducing the first self-winding chronograph model in its history. The newly launched reference 16520 was powered by a derivative of Zenith's El Primero caliber, though substantially modified by Rolex. It was the first Daytona to be equipped with a sapphire crystal and featured a new, larger case incorporating crown guards for the first time and measuring 39mm.

The launch of the 16520 was an immediate success, resulting in unprecedented demand that would require clients to have to wait as long as seven years to purchase one. This was quite in contrast to the initial lukewarm response of the manually-wound Daytona, first introduced in 1963.

As is the case with many other Rolex models, and part of what makes collecting vintage Rolex so exciting, there are subtle variations to the reference 16520 that can significantly increase its collectability. The present example possesses one of the most desirable traits, a pleasing aging to the sub-dials, nicknamed "tropical", seen only within a certain range of serial numbers. It is believed to be the result of a production defect, with the paint not properly resisting the effects of the UV rays in sunlight and exposure to oxygen, therefore changing color. This desirable defect is not present or possible in all reference 16520s, and are typically only found in black dial, stainless steel examples from between 1993 and 1996. An exceptional example for the connoisseur, it remains in truly “new old stock” condition, having never been worn and still retaining the original stickers on the case and bracelet as delivered by the factory. Furthermore, the present watch is fresh-to-the-market, consigned by the original owner.