Williams was following the Walden and Mossberg line of automobile tools.
they made that same style in 1916, listed as 970A 9/16" it was listed as;
Williams Drop Forged single head offset pattern socket wrench.
Alloy Artifacts shows 2 wrenches of that style, I think they were 5/8" & 7/8" ????
I have some Walden's and some Mossberg's in that style. I am not sure if Bog made any like that.