Now I get it. That labeling is confusing. You want to know which chicken stock is used in Whiting Soft Hackle with Chickabou packaging.
After reading the Whiting product pages and Feather Emporium's more extensive information, the information is ambiguous. The packages labeled "Soft Hackle" could be Brahma Hen, Whiting stock, Hebert Minor stock, American Hackle stock, or anything. Feather Emporium says that Whiting Soft Hackle with Chickabou is Whiting or Heber-Minor genetic stock which is different from Brahma Hen stock and Coq de Leon stock. Should be explained by Whiting somewhere though.
Here's Feather Emporium's photo of the different Whiting hen lines which you've probably already seen:
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