Around 1988, Rolex decided to discontinue the classic Daytona manual wind model. They replaced it with a brand model that featured a new automatic movement. At the time, Rolex was not producing an in-house automatic chronograph movement so they used the very reliable Zenith based movement (Caliber 4030). In the first models they introduced, the new Daytonas featured a specific dial design that would be quickly discontinued (after approximately two years). They are instantly recognizable by the word Cosmograph, which is clearly detached from the rest of the writing. This dial version became known to collectors as the "floating Cosmograph". This watch has several features available only in the reference 1652?s produced from circa 1988 to 1990: - Porcelain Dial - "Floating" Cosmograph - Chronograph hour dial number 6 inverted - Bezel with tachometer scale graduated to 200 UPH