The 6238 is considered to be the pre-Daytona reference; most of the aesthetic codes were already in place, starting with the Oyster case and the pump pushers. It was already powered by a Valjoux 72, the main difference is the inner tachymeter, which the first Daytona would display on its bezel. This reference is actually quite rare, as it is estimated that roughly 2,000 (a fairly low number for Rolex production) examples of these were made throughout the 1960s. Of those 2,000, most did not age gracefully, further emphasizing the rarity of finding a piece in such pristine condition as this example. Daytona lovers might be offended, but in our book, the silver 6238 might be one of the most elegant chronos that Rolex ever made. This one comes from the family (grandson) of the first owner. All original and just been full and carefully serviced by my superb watchmaker.