For the second time in as many years, the federal government’s car safety watchdog is warning Americans not to buy decorative steering wheel emblems.

Small plastic or metal steering wheel decals that mimic your car’s logo in shiny rhinestones are popular on Amazon and other online stores. They cost as little as $6.99, and the National Highway Traffic Safety Administration (NHTSA) says they’ve seriously injured some drivers.

The problem, the agency says, is that your steering wheel is designed to let an airbag explode through it in an accident. Anything attached to its surface can become a projectile when that happens.

Even the automakers that design and build cars had to learn not to put detachable emblems on steering wheel covers. Both Chevrolet and Nissan have had flying emblems recalled in recent years.

Aftermarket decals have contributed to horrific injuries.

NHTSA warns that one driver recently lost an eye to rhinestone shrapnel. A second had two pieces of an aftermarket logo removed from their face and neck after an accident.

Yes, it’s graphic. We give you those images to drive the point home. NHTSA warns drivers to “avoid purchasing these steering wheel decals for all vehicle makes and models. Consumers should also remove any such decals that they have already applied to their steering wheels.”