Bolo Ties refer to a Thin rope of leather worn like a lariat, Draped around your neck and held together in the center with a fancy clip like turquoise stones, steer heads,, eagles, or any other "western" influence that could be proudly displayed.
The 1980 movie Urban Cowboy, starring John Travolta and Debra Winger had influenced the use of Bolo ties, and other "cowboy look" clothing and accessories, such as cowboy boots and hats, fringed leather jackets, etc. The Duckie character played by Jon Cryer also wore a Bolo tie with a big black stone in the 1986 movie Pretty in Pink.
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