I HAVE HUNDREDS OF TIE TACKS, TIE BARS AND CUFF LINKS. cuff links: 0.76" x 0.75" (3/4" x 3/4" or 19mm x 18.5mm). I always try to point out any clear blemishes and condition. 0.25" = 1/4" or 6mm - pretty small for standard button holes.
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