Despite a warning regulators issued last fall to avoid using steering wheel decals, another driver suffered severe injuries from such an add-on in a recent crash.

The National Highway Transportation Safety Board repeated its caution about the decals after the incident, which it said involved an air bag deployment that sent two pieces of a metal rhinestone-studded decal into the driver’s face and neck.

The U.S. transportation department agency again advised motorists to avoid such decals due to the risk of similar incidents. It issued its first warning in November after a driver lost sight in one eye from a decal sent flying in an accident.

The adhesive after-market add-ons aren’t permanently affixed like manufacturers’ emblems, the agency pointed out. Instead, in a crash, a deploying air bag can dislodge them from the steering wheel, turning them into projectiles that can cause serious injury or even death.

It advised consumers to remove any existing decals from their steering wheels and avoid buying them for any make or model.

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