Mechanism: The 1575 is the date version of the 1570. Like many rolex movements the date version will be stamped with the same number as the non-date version. Hence you will see "1570" stamped into most (if not all) 1575 movements. The sure fire way to tell the difference is the presence of the date wheel.

The 1570 movement superseded the 1560, but shared the vast majority of its elements, with a few notable improvements. The 1570 marked the third generation of the 1500 series. It comes with the balance assembly Rolex p/n 8106, again with a Breguet hairspring. However, it’s with a higher frequency of 19,800 bph, or 2.75Hz.

Similarly to its predecessor, Rolex also manufactured it as a date and GMT version, the 1575, which proved the perfect companion to the Explorer II released in 1971, as well as the GMT-Master and Datejust series. As with many of the date equipped mechanism made by Rolex, the number stamped into the metal is the NON-date version. Hence in the case of the 1575, the mechanism will be stamped "1570".

Although there is no Quickset mechanism, the 1500 calibers came with the cam and jewel system. This system was able to create an instantaneous date change at midnight, still used by Rolex today.

Family Notes: The Rolex "Date" family of watches are smaller and less expensive than their cousins, the "Datejust" family. Date watches are enclosed in 34mm cases, whereas Datejust models are in 36mm cases. Furthermore, the Date models use 19mm width straps while the larger Datejust models use 20mm straps.

Being the less expensive line, new features reach the Date family only after the Datejust watches have already adapted them. For example, the Datejust family received mechanisms with Quickset date capability years before the Date models did.