I HAVE HUNDREDS OF TIE TACKS, TIE BARS AND CUFF LINKS. tie tack/bar: 2.16" x 0.30" (2-1/8" x 5/16" or 54.5mm x 7.5mm). 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.
