But am I correct in understanding that American watches generally received downgraded 17 jewel variants?
In some cases, they did. However, I think this had more to do with how a particular model was marketed in the U.S. and the price points vs. other competitors.
You have to remember that prior to 1970, you had hundreds of watch companies, from Switzerland, USA, Japan, Germany and other countries producing watches in the mid-market price points. At that time, that could be anywhere from $50 to $500 (again, 1970 and earlier dollars).
Tariffs on imported watch movements were not charged on the first 17 jewels, but if a movement had more that 17 jewels, the tariff applied to all the jewels, including the first 17, that would otherwise be tax-free. So let’s say that the total import tax on a steel cased watch was $10. This doesn’t sound like much today, but if the watch was competitively priced at $100 retail, that’s a big cost. If an importer could avoid that by downgrading the movement a bit without affecting selling price, that’s 10% saved. That’s a big savings where margins at the wholesale level were probably 15% or less.
A lot of Swiss watch companies would sent 17 jewel versions here a raw movements, have their importers purchase US made cases and utilize US watchmakers to adjust and case the watch. Omega, Jaeger-LeCoultre, Girard Perregaux, Longines and even Rolex did this. Some movements would be marked “Unadjusted” to avoid this tariff, yet in fact they were adjusted, but it was done here in the U.S. This is sometimes called “National Production” and you’ll see it referenced here quite a bit.
You should read this series of articles with illustrations of how this was done with respect to LeCoultre watches sold in the U.S.
https://blommanwatchreport.com/2019/11/21/jaeger-lecoultre-and-the-u-s-market-part-3/
American companies like Hamilton, Gruen, Bulova, Elgin and Waltham started importing Swiss movements (especially automatics, since the U.S. companies were notoriously slow to develop their own) after WWII and did much the same thing.
The U.S. was not the only country with high tariffs on imported watches. France, UK, Spain, Argentina, Brazil and Australia had similar taxes. But only the U.S. had this system based on 17 jewels, and since it was the largest market in the world, many of the Swiss watch companies danced to the same tune.
Hope this helps with your understanding of why U.S. movements may be different for some vintage watch brands.
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