A better question would be, what companies that are not part of these conglomerates make tools in the USA. Wright and Klein are all that I can think of.
If we're talking about actual tool makers, there are several I can think of. Most of them aren't as well known brands themselves but I think make most of their money by having their tools relabeled by the better known brands.
Almost all of these companies still try to build their own brand as well, filling out their catalogue by relabeling tools from other suppliers as well. It seems like a lot of tool manufacturers specialize in making a couple types of tools themselves, licensing them out to others, and then also relabeling other tools from other manufacturers. I've tried to start drawing a map of who actually makes what and who sells what, but it was a very tall order, because almost all tool companies are a mix of making things themselves and licensing from others. They usually aren't very clear in their website or catalogue about what's what.
Some of these tool manufacturers in the US include Wilde, Enderes, Alfa Tools, Mayhew, Western Forge (owned by Ideal Industries), Cornwell, and Central Tools, just to name a few I've bought recently.
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