What a nice collection of Shanghai watches!

The first two appear to be later versions of the 7120, probably dating to the 1980s. They contain the tongji, a movement which was also called SS7 or ZSH when it was made by Shanghai Watch Factory. You can determine the dates of the movements from the two-letter code under the balances.

The A631 was a midsize watch which began production in 1963. It has a similar movement to the more common full-size 611 models. They're not easy to find. 6510 tells us the movement was manufactured in October 1965. It'll be 60 years old soon.

The SS1 movement was introduced in 1966, and the earliest SS1 watches were given the designation SS1A. Beginning sometime (April-ish?) in 1967, SS1A watches became the 11xx series. With a date code of AH (August 1966), yours might be the earliest example I've seen. And what an example! Black dial SS1 watches are rare and desirable.

From your pictures, I don't see anything to suggest that any part of these watches shouldn't be there. However, I'd like to ask an expert for more information about the A631. If only I could find one.

 

Thanks very much for all the info, really appreciated. Because of the good condition they are all in, with me knowing nothing about the brand, I surmised that they are probably a lot younger! The SS1A is probably my favourite given that it works so reliably and accurately. It's the one I wear from time to time (I have way too many watches so they have to wait their turn for wrist time!). The '63 Seagull Chrono is what has got me interested in Chinese Watchmaking, such an interesting and beautiful watch! So when these four came along I had to get them, a good way to start I thought!
Looks like I'm entering another rabbit hole...

thanks again and
very best regards
Geoff D
Merimbula, Australia

 

Thanks. A quick correction: I said, "The first two appear to be later versions of the 7120". The 7120 didn't have a calendar function, so the first is not a 7120. Shanghai tongji watches with single calendar were designated 7221 (quick-set) or 7220 (slow-set). Yours is almost certainly the latter. Most 7220s didn't have a model number inscribed anywhere on the watch.

 

Excellent, thanks for that
I've now checked the date codes on the first two as well:

LEFT: MK (coming up as November 1976)
MIDDLE: AH (coming up as August 1966?)

what do you think?

regards
Geoff