Since Louis has raised the topic of 12-size Waltham-Howards, this is a good time to look if you have one of these laying unrecognized in your collection. Out of a few hundred made (very rough estimate) I have only recorded twenty-three bridge model movements and thirteen 3/4-plate movements in 12-size. Until I record more examples my production quantities, production dates and variations are pretty sketchy.
The 12-size bridge models have serial numbers in the low 816-thousands, usually with an "H" prefix (as shown in posts above), and in the low millions (1,020,xxx or 1,025,xxx) as shown directly above. Although some have the "E.Howard & Co." name, many have had the name removed. Be careful with the millions group as Keystone used some of those numbers over again for their own watches later on.
3/4-plate movements used a plate pattern in common with Waltham's Equity movements. Serial numbers are 866,801 to 867,100 (with or without an "H" prefix) and again in the low millions (1,030,xxx and 1,035,xxx). They may be marked "E.Howard & Co" or may also have had the name removed.
If you have one of these consider yourself fortunate and, please, share your watch information so that I can complete my research on these.
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