Have you ever tried to use this to defend yourself at night? I've got a better option for you. People use this to defend themselves, but the problem with that is the moment you hit something, it cuts into your own skin. Now something like this is used to break windows in a car, but it's also very effective for self-defense. You're going to move your side sideways, and you stab. Now if you have none of that, the best thing you can do in these kinds of situations is go for the neck.