I located mine today. it is also 12" on the upper jaw; "COE'S WRENCH CO. Worcester, MASS. USA
on the oposite side of the upper jaw; AUTO COE'S inside the wheel.
so far, have not seen any other markings on it.
I will have to start checking my other wrenches after seeing the 6" that Stan put up. with the adjusting nut
in a differant location, I may have missed one.
being only about 36 miles from Worcester, ya never know whats out there.