A collar pin (also called collar bar and collar clip) is a piece of men's jewelry that holds the two ends of a dress shirt collar together and passes underneath the knot of a necktie.
Functioning in a similar way as a tabbed collar, it keeps the collar in place and lifts the knot to provide a more aesthetically pleasing arc to the necktie.
A collar pin is between three and five centimeters in length and is one of three kinds:
The latter two styles do not require specially made collars, but collar bars are generally not worn with buttoned-down collars and would be redundant with tabbed collars. Collar stays are not needed when using a collar bar.
Collar pins of the safety pin variety were fashionable in the early / middle 20th Century. Soft shirt collars often curled up of their own accord and before the advent of button down collars, such 'tie' pins were usually part of men's and boy's 'Sunday-best' attire.