I have one of these in my collection.
I can't give you a firm date, though I believe it to be prior to WW-II. This was a common style of adjustable wrench, aka Monkey Wrench, before the Crescent Wrench (modern 30 degree offset adjustable wrench) displaced it. These wrenches usually had longer handles, and the smaller bicycle versions were made for convenience and qualify as the "mini-wrenches" of their day.
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Can you open the jaws and post a photo of it? I'm assuming there is a straight shaft that operates the jaws, but was curious if there is another feature that helps keep it stable (like a tongue and groove slide). Seems like if it only had the shaft, the play due to required clearance would be exaggerated at the jaws and lead to rounding of nut. But maybe it's constructed with very little play. Anyway, neat little tool.