I HAVE HUNDREDS OF TIE TACKS, TIE BARS AND CUFF LINKS. tie tack/bar: 1.99" x 0.52" (approx. 2" x 1/2" or 51m x 13mm). collar bar: none. 0.25" = 1/4" or 6mm - pretty small for standard button holes. I always try to point out any clear blemishes and condition.