car seat safety regulations

Do regulations restrict the attachment of items to the rear of the front seat of a car?

I am trying to find out whether there are any state or federal safety regulations which deal with attachments to the rear of the front seat of a car. Specifically, I am looking at attaching something to the base of the headrest of the front seat, which hangs down the back of the front seat from the headrest, for the benefit of passengers in the back seat. Thanks.

No regulations. But be sure that what ever you hang is secured. It becomes a projectile to the front seat passengers in an accident.

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