I found this 8-inch Herbrand wrench today in the litter on my workbench. The openings are 15/16" (closed end) and 1/2" (open end). It looks, from the typeface on the bosses, that the wrench was produced sometime before 1900. It also appears to have been finished on a Monday, or by a novice.
The letter N is backwards in the words Herbrand and Fremont. Also, the number 993, was botched during the embossing step.
The wrench appears to be designed for a specific purpose. Does anyone know what that was?