Here is an interesting old Bulova, 21J 7AP movement with a X date code, Satin White dial with printed Black numbers, minute tracks and Blued hands.
The Gold Bulova caseback is marked 10K Gold filled, and the band is a Kreisler quality.025 Gold content rice bead style.
The GS CX756-80 crystal snapped right in the flat bezel.
This old Bulova came with a lot of 4 other watches and was missing the crown and stem. Once replaced and wound it took right off and has been running super since.
In reply to OT, shouldn't this be listed by DarHin
DarHin Good question. If we disregard the movement date and just look at relationship of first digit of case SN relating to year of production, I think the correlation is not as strong or maybe non-existent by 1947, as some, but not all cases have the date stamp 46, 47, 48 (A8), and 49 (A9) (J9) for those years. Having said that (and since there isn't one of these stamps on the case) would subject case SN suggest 1937? ...or do we guesstimate date by knowing when these cases were available/made during this cusp date range? It could be a 1947 case, not marked with the 47, which, coincidentally has a case SN beginning with a 7. ...or the correlation exists during this period and I forgot that it exists.