That's quite cool looking. But I wouldn't want to count on it for self protection. You are dependant on the bad guy playing by your rules. They have to stay back away from you by just the right amount, present their unprotected head for a clean shot, and keep their arms down so it doesn't just harmlessly wrap around a few times. Most criminals aren't very smart and probably wouldn't figure this out, but stepping forward *towards* you would completely defeat this device.