Just received this in an email. Don't know if it's true, but the headrests in my car
fit the description. Being old with limited strength I found this info good to know
in an emergency.
"The headrests of car seats are deliberately detachable so the metal anchor spikes can
be used to break car windows in case of fire or an emergency. Also the car's glass is
more easily broken from the inside."
As I said, don't know if it's true but I can't think of anything else inside my car
that would help me in an emergency.