Vintage brooch is a replica of a Snap On tools full-size combination open and box ends wrench. It is marked 1/4 and indeed is that size wrench, and could be used to turn a quarter inch bolt.
This piece measures 1.25 inches by .5 of an inch.
Marked with the Snap On logo.
A really fun piece, and would be a great gift for a DIY repair oriented person.
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