It is the truck company, the script is distinctive with a loop flourish conecting the capitol W with the h. It is also J.H.Williams, the W in a diampnd forge mark is williams. Perhaps a misstamping on the name. That wrench in that size is on Alloy Artifacts BTW.
> [bolt sizes?]
Yes, #729 standard size wrench for 7/16&1/2 bolts
To date it, need to know what it says under williams, if anything...
The very small W in the diamond mostly appears before 1914 ish, but not conclusive...
Stray weird trivia, in the 30's, White was run by a fellow named Black....