Shanghai Watch Factory produced the 15 series of watches in the early 1970s. It appears that the model designation referred to watches containing the new fast-beat SS1A-K, but a number of 1523 models have slow-beat SS1 movements. I have one of them, and I wanted to get a fast-beat model too.

21600 is printed on the dial, indicating the beat rate of the movement inside.

The 1523 has one of my favourite SWF casebacks.


The date code is GH (August 1972).
After production of the 1523 began, the factory introduced the 1524.

I don’t know why, but the 1524 usually sells for less than other SS1 models. This one has an early caseback.



The fast-beat SS1A-K has a date code of HA, January 1973.