Housing a “Mark II” black dial, the present lot was made two years after reference 16520 was introduced. The present lot is fitted with a highly attractive and uncommon “Mark II” black dial in excellent condition. There are several characteristics that make the “Mark II” widely revered nowadays. First of all, the dial configuration was only made for a limited period of time and fitted on very few early L serial 16520 Daytonas, making it an extremely scarce configuration to own. Additionally, the lettering “Officially Certified” is left out of the dial, a trait that distinguishes this dial from the previous Mark I design.

Most noticeably, the "Cosmograph" designation is now together with the rest of the writing on the top of the dial, different from the earlier “floating cosmograph” design. The subsidiary dials contain the same characteristics as the Mark I dial, such as the upside down "6" digit on the lower subsidiary register. The present watch is fitted with a “Mark II” bezel, with scale up to 400 units/hour with measurements at intervals of 1 unit up to 100 and intermediate at 225 and 250, which is period correct for the L serial. This watch has been preserved in excellent condition with full proportions and a crisp case, with its original caseback sticker still retained.