The metal bars hanging beneath the back-end of 18-wheelers are named after a famous actress of the 1950s and 1960s. The bars are called "Mansfield Bars". They've been around since the early 1950s but public outcry made them mandatory in 1967 because of a horrible accident east of New Orleans, Louisiana.

Jayne Mansfield
Photo by Harry Benson/Getty Images

Jayne Mansfield was a popular Hollywood starlet whose career many compared to Marilyn Monroe. Mansfield resembled Monroe in appearance because of her blonde hair and curvaceous figure.

Jayne Mansfield
Photo by Hulton Archive/Getty Images

Jayne Mansfield was at the height of her career in the mid-1960s, but all that changed on a roadway just outside of New Orleans on a foggy morning in 1967.

Mansfield was a passenger in the front seat of a 1966 Buick Electra along with her lawyer and companion, Samuel S. Brody. Her driver was Ronald B. Harrison. Mansfield's three children were asleep in the back seat.

Jayne Mansfield had performed at a dinner club in Biloxi, Mississippi the night before. It was just after 2 a.m. and the actress was due in New Orleans for an early morning television interview.

Investigators claim a truck in front of Mansfield's car on U.S. Route 90 east of New Orleans, more than likely slowed down for a truck spraying for mosquitos and that's when the Buick carrying Mansfield and passengers slid under the back end of the tractor-trailer.

Jayne Mansfield Car Crash
Photo by Keystone/Hulton Archive/Getty Images

Mansfield and the two men in the front seat were killed instantly. The three children asleep in the backseat sustained injuries but survived.

Mansfield Bars
Staff Photo

After Mansfield's death in 1967, the public outcry for undercarriage bars made for tighter enforcement of what's now known as the "Mansfield Bars". The National Highway Traffic Safety Administration made "Mansfield Bars" mandatory on all semi-truck trailers.


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