Head restraints reduce the whiplash effect caused by a rear-impact crash. If they are set at the right level for the driver, they perform very well. Adjusting the restraint properly is critical for good protection.
According to State Farm Auto Insurance, the space between the back of your head and the front of the head restraint should be no more than four inches. The restraint should be as high as your head's center of gravity, which is about three inches below the top of your head.
