I HAVE HUNDREDS OF TIE TACKS, TIE BARS AND CUFF LINKS. tie tack/bar: 1.61" x 1.02" (1-5/8" x 1" or 40.5mm x 25.5mm). collar bar: none. I always try to point out any clear blemishes and condition. 0.25" = 1/4" or 6mm - pretty small for standard button holes.