When I was in Spain a favorite tool of thieves who broke into cars was a spark plug. Apparently it doesn't take a lot of force to break a window if that force impacts at a single point. My Spyderco Assist 1 has a carbide tip that is exposed when you squeeze on the closed knife. It doesn't take a lot of force and it's much safer to wield than a Life Hammer IMO. I have a pair of leather/nomex gloves to provide a bit of protection from both the broken glass and any flames that may be present. Hopefully, I'm on the outside, but I keep that stuff in my truck's console if I'm on the inside.
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