I got this combination wrench set (No. KC5A) as the receiving end of a trade with
@RTM last year, neglecting to post it here in the MAC thread until now. He did upthread, but I will elaborate.
Note that the largest wrench, the No. C5 (1/2"), is branded exactly the same, in the same style, format. and placement as the others, but i's forged-in, whereas the branding on the others are stamped. All the wrenches have the sizes forged-in. Note that it also has a double-hex (12-point) broach, whereas all the others are hex (6-point) broach. I have little to no doubt (and, given the circumstances of its finding, no reason to doubt) that all the wrenches are original to each other and the leatherette pouch. I suspected it was assembled in a transition period and I am very confident that was sometime in the late mid 1940's to the late 1940's, prior to 1952.
The catalog excerpts below are from the Mechanics Tool & Forge Catalog No. 47 (published in 1947). The model numbers on the wrenches ("C1" through "C5") match the model numbering scheme in the catalog. All the wrenches in the catalog have a 12-point box end, but we know from a larger combination wrench set (No. KC11) that
@Oldtuleguy acquired, linked
here, that the smaller wrenches (C1 through C4) were made with a 6-point box end broach.
Interestingly, OTG also has the same No. KC5A set as this, linked
here. In his set, though, the brandings on the No. C5 wrench are stamped, just like the other wrenches. At some point, I'm assuming all the wrenches had forged-in brandings, and it might've been earlier.
While the combo wrench set pouch is not shown with the branding in the catalog, the open end wrench sets do show it, also helping to date it.
In the 1952 catalog, the combination wrenches have two different part numbers "CWx" for 12-point and "CHx" for 6-point.