You know that long strap that always gets stuck in car doors and under your feet when you’re moving your car seat around? That annoying guy is a lifesaver. Intended to be attached to anchors that usually sit behind the headrests (almost all tethers are only used with forward-facing car seats), the tether keeps your little ones head safely within the confines of the seat, yet only 42% of parents use it.

“Using the tether decreases how far the child heads moves forward by four to eight inches with a properly installed car seat,” says Dr. Baer. “That doesn’t sound like much, but it could keep your child’s head from hitting the back of the front seat, the door frame or window in a crash, and that’s the key to decreasing your child’s chance of having a brain or spinal cord injury.” With an improperly installed seat, the benefit of the tether is even greater, says Dr. Baer.

The fix: All forward-facing car seats (and a few rear-facing too—check your manual) should be tethered to the proper anchor for the car seat’s position in the car. Once again, get out your car seat and car’s manual, and install the tether according to both sets of directions.