What would you call a swivel flange outside of the US that is more of a ducting flange with no gramophone or raised face or anything, just a laser cut flange.
Well if all you meant was the ring bit, I would call that the backing ring. If someone called out a " plate flange" I wouldn't have known what it was and I'm outside of the US.
Interesting how the same thing can have so many different names....
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