Notes: The 1675, produced between 1959 and 1980, is one of the most striking of the Rolex GMT-Master watches. Not only did this watch enjoy one of the longest production runs in Rolex history; it also is one of the most easily-recognized because of its beautiful blue and red bezel. Because of the bezel colors, this model is known as a "Pepsi".

For the first ten years of production the Rolex GMT Master 1675 featured a small triangle on the extra hour hand. This was succeeded by a red hand with a larger triangle in the 1970s and is one of the easiest identifying points in helping to date this watch. Earlier models also featured pointed crown guards as well as a chapter ring. The very earliest Rolex GMT Masters were produced with a Bakelite bezel, but the Ref. 1675 has always had a metal bezel for sturdiness and stability.

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The 1570 movement superseded the 1560, but shared the vast majority of its elements, with a few notable improvements.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.