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RDS's avatar

Great article. I just bought a 43999 AD. How can I ascertain the production date? Thanks.

The Grand Seiko Guy's avatar

Thanks! First two digits of the case back serial number indicate year and month. So for example 43… would be March 1964.

RDS's avatar

My serial number is 5201299. Your chart says no 43999’s were not produced in February 1965. What do you think about my example? Thanks.

Christoph's avatar

Great, thank you so much! Any hope for the second part?

John Cochran's avatar

Great write up, thank you! I have a December 1964 AD 43999 with the 5722a purchased through yahoo auctions and I just love the watch. It’s the first vintage GS that grabbed me and it’s just so perfect.

The Grand Seiko Guy's avatar

Congratulations John. Yeah the 57GS often gets overlooked, but they are fabulous pieces, and the good news is that most variants are pretty easy to come by so they are superb value for money.