I HAVE HUNDREDS OF TIE TACKS, TIE BARS AND CUFF LINKS. tie tack/bar: 1.64" x 0.53" (1-5/8" x 1/2" or 41.5mm x 13.5mm). collar bar: none. 0.25" = 1/4" or 6mm - pretty small for standard button holes. 0.38" = 3/8" or 9mm - also fits standard button holes.
