This black dial, stainless Rolex Cosmograph Daytona ref. 116520 occupies rarified air in the nuanced world of Rolex collecting. Introduced in 2000 it's the very first reference number to use the Rolex in-house, automatic, chronometer-rated, column-wheel chronograph movement, the caliber 4130. There are an ocean of Daytona references but for the sake of simplicity we can divide them into three movements and the corresponding eras. From 1963 - 1988 Daytonas were Valjoux-sourced manual wind calibers; From 1988 - 2000 Rolex used a Zenith El Primero automatic caliber 400, which it then heavily modified and renamed the Rolex caliber 4030; and from 2000 to present the fully in-house, Rolex designed and manufactured automatic caliber 4130. The mechanics established, notice the bezel on this watch - the numerals are all aligned so that they remain upright all the way around the dial, which is the old school look. The new bezel style with the numerals all oriented toward the center of the dial began in 2004 and over the course of a dozen-odd years was adopted to all Daytonas. So with the same cases and bezels how do you tell a 116520 from the Zenith era ref. 16520? It's really simple, actually. The running seconds sub dial on the 116520 is at the 6 position while on the Zenith piece it's at the 9. Another little sign is that the sub dials at 3 and 6 are slightly higher on the 116520 given the mechanics of the movement, which really is the crux of this piece. The Rolex patented screw-down, Triplock crown, 18 carat white gold hands and baton hour markers, arrow-tipped chronograph hand, and the red "Daytona" at 6 are really just wonderful little details. As are the sub dials, which deserve a special note. A small design element common to all Daytona Cosmographs is sub dials that in some way contrast the dial. In this case the numeral track is "silver" to match the bezel, "snailed" with engraved concentric circles and outlined by white gold rings. In 1963 when the Cosmograph was brand new this might have seemed an odd design flourish but it was more utilitarian than fashionable. The watch was purposely designed for professional racing drivers to wear on-track to calculate speed and time laps during a race so at a glance contrasting dials were easier to read. Originally known only as the Cosmograph, the "Daytona" moniker found it's way to the dial in 1964 during the third year of Rolex's sponsorship of what is now known as the Rolex 24 At Daytona endurance race. The 116520 is as vintage looking as any modern Daytona can be and wearing it you get the sense that you're not far from the original, that somehow you're in the 1960s wearing skinny pants making photos with a film camera. As an aside, in the mid-1960s full retail on a Daytona was $210 USD including federal tax, and jewelers were discounting that because no one wanted them. A vintage reference Daytona will set you back low-mid six figures at auction these days and that's for a watch you wear gingerly or perhaps not at all. The 116520 was Rolex's promise to the Daytona line that it would endure so Rolex wants you to wear it and use it and time things with it and enjoy it. Iconic is not too strong a word in this case.