A tie bar (also tie slide, tie clip, or tie clasp) is a clothing accessory that is used to clip a tie to the underlying shirt front, preventing it from swinging and ensuring that the tie hangs straightly.
Tie bars are commonly made of metal and sometimes have decorative patterns or embellishments. Some clips have a small badge indicating membership to a club or some other affiliation, or some other commemorative token, in a similar manner to the way in which ties themselves may be used as signs of membership. The use of tie clips gained prominence during the 1920s, during which period the use of straight ties made of delicate materials such as silk became more fashionable, and they largely came to replace the more traditional tie pin. Check here how to wear a tie bar and here for a great selection. (pics by Tommy Ton for GQ)