"You may need one only once in your lifetime"

I have a relatively long line of sharp shooters in my family, but that all stopped during my mom's generation, and I have never been to keen on guns. I stumbled upon this ad today, and thought it was nuts. Quotes like "accidental discharge impossible," and "you may need one only once in your lifetime" are rather disturbing. Knock on wood, but I am hoping that I never need one.