I HAVE HUNDREDS OF TIE TACKS, TIE BARS AND CUFF LINKS. tie tack/bar: 2.70" x 0.30" (2-11/16" x 5/16" or 68mm x 7.5mm). collar bar: none. 0.25" = 1/4" or 6mm - pretty small for standard button holes. 0.50" = 1/2" or 12.5mm -this is fairly large for standard button holes.
