General Plastics (Beauclaire) did not feature their buckles in advertising, which seems strange. The advertising was nearly all about the buttons; if you look closely, carded buckles could be seen on the “button merry-go rounds”s illustrated in some ads. If belts were shown on the models in their ads, they were narrow, without fancy buckles, except in a 1957 ad featuring a very glamorous belt. See the Beauclaire advertising page if you are interested. I guess by sheer numbers, buttons were the big money earners. An outfit could feature dozens of buttons, but only one buckle, and belts could be used for multiple outfits.
G.Herring (Beutron) did mention and picture their buckles more often, but it was still mostly about the buttons for them, too.
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