A tie bar (also tie slide, tie clip, or tie clasp) is a neckwear accessory that clips a tie to the fold of a shirt, preventing it from swinging and ensuring the tie hangs straight, resulting in a neat, uniform appearance. Rising to prominence in the 1920s, the tie bar is typically worn by necktie wearing professionals.
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Other References:
http://www.tiealign.com
http://www.tie-a-tie.net/accessories.html
