(5/16" or 7.5mm). I HAVE HUNDREDS OF TIE TACKS, TIE BARS AND CUFF LINKS. I always try to point out any clear blemishes and condition. tie tack/bar: none. Color:gold, gray. Condition: VERY GOOD, stud slides are smooth and springs consistent - SEE PICS - (Hi resolution photos typically show more detail than is visible to the naked eye).
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