Double Beat / safety escape tool with car

When accidents happen, the people on board need to escape by breaking the glass. This is a secondary-impact safety hammer to be used in an emergency to crack the glass as fast as possible.
Due to the use of the laminated glass for windshields of cars, there are plastic films between two pieces of toughened glass ,people have to crack the glass at the exact same point for dozens of times .
Double beats takes advantages of the principle of inertia. When the metal awl hit the surface of the glass, because of the inertia, the metal cube behind will hit the hammer again.