Please post if Zenith Responds. I'd be curious as, I have the 706D623 pictured above. As fate would have it, I am moving to Switzerland in September. If they don't respond by then, perhaps I will take a ride to Le Locle so I can present the watch and ask in person. Thanks!!!
Good news, I actually just heard back from them today.
Bad news, they pointed me to simply getting an Extract from the Registers. Depending on who at Zenith replies, on occasion more information is provided, but unfortunately was not the case this time. The Extract from the Registers (or Archives, long ago) would sometimes provide a case description (including caseback information). On the newer Extracts (2020) I have never seen any case description, unfortunately.
Currently Zenith Extracts provide "the
model, the
functions, the
calibre, and the
production date corresponding to the movement and case serial numbers of your timepiece in the Zenith Registers", which won't help us in this situation.
The Certificate of Origin might, but I can't say conclusively (and I've never actually seen a Zenith Certificate of Origin - if anyone out there has one, please share!). Zenith states that a CoO "will enable you to
certify that the movement, the case and the dial of your timepieces originate from Zenith. It will be issued along with a detailed description of the
model, the
functions, the
calibre, the
case, the
dial and the
production date of your timepiece, based on data from the Registers and the Archives of the Manufacture, complemented by a meticulous analysis of your timepiece by our watchmaking experts in Le Locle." However, assuming the caseback is of Zenith origin, but not intended for the A386, it does not seem they would indicate. At least that is my read...
Would be interesting to see how they would respond to the direct questions whether the caseback is i. correct for that case number and ii. if it was intended for the A386. If you get there
@Charger_Vital , please let us know!
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