> probably C.E. Bonner company out of Illinois
Probably
>old automotive wrench
S- wrenches were the standard pattern for quite some time
It is different from anything I have seen
One end shows unmistakable signs of having been modified, the other (square) end is odd however, there is a lot of metal left, so it was originally quite small and made square, or was in fact originally square, which would be a somewhat odd pattern.
But, from what little I have run across of Bonner, they occasionally made strange and unusual things...
(I had more info and photos on the old forum, sigh)
their ad logo (later) was "Bonner quality tools", googling that in books will find you some ads I think...