Our window punches are made of Stainless steel with heat hardened tip designed for maximum effectiveness on automotive tempered glass. Window punch tools are carried in every police, fire and ambulance vehicle. The Window Punch operates by simply placing the hardened tip on the glass, pulling back on the spring and letting go. The Glass then shatters into a web pattern and can be easily removed without injury to you or others around. Ideal for getting out of a trapped car where the doors will not open and time is critical.