Owners of used vehicles are being warned to have their air bags inspected to ensure they’re genuine after three recent deaths of travelers killed by faulty bags.

The National Highway Traffic Safety Administration said some original air bags have been replaced with versions that include substandard inflators, many of which were made outside the U.S. It said that in addition to three deaths caused by such bags in the past nine months, two people have suffered disfiguring injuries.

The federal agency said all of the vehicles involved in the crashes had been in previous wrecks and had their air bags replaced with defective equipment.

“These dangerous aftermarket parts malfunctioned in subsequent crashes, sending large metal fragments into drivers’ chests, necks, eyes and faces, killing or severely injuring drivers in otherwise survivable crashes,” NHTSA said.

Such substandard air bags are typically made by overseas companies with limited or no track record of quality product and experience, are sold online at well under the prices of genuine counterparts, and installed by shops without strong reputations, such as those run by dealerships, the agency said. The air bags can partially or slowly deploy and therefore not protect occupants’ heads from hitting the steering wheel or dashboard.

It urges consumers who already own used vehicles or are in the market for them to research their histories to ensure they contain genuine air bag inflators. If they determine theirs may contain defective parts, they should contact a dealership of that vehicle brand or another reputable repair shop to learn if they should be replaced.

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