I HAVE HUNDREDS OF TIE TACKS, TIE BARS AND CUFF LINKS. cuff links: none. 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.
The BSA Boy Scouts Fleur de Lis Vintage Tie Tack Lapel Pin of America t49 would be a perfect fit for collectors of Boy Scout memorabilia.