When You google "vintage Buckeye tools" and turn on the image view, a few of these show up. Also many with other "ends" too.That looks maybe like some kind of spud wrench/key, for utilities. Hydrants. Drains. Water main. Gas. Etc. Perhaps. Buckeye Mfg made jacks, also wrenches.
Yup. Each one fit a unique opening. The small one is actually a quoin, for letterpresses. But same concept.Also many with other "ends" too.

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