This unique book is the fore runner of the famous Kubotan. It was written in the 1940's by Professor Frank A. Matsuyama. It was intended for the Police forces and the many techniques taught in this little book are everything from strikes to locks and even throws plus a lot lot more. Once you have trained in the Japanese Art Of Yawara by Professor Frank A. Matsuyama, you will totally understand the power of this little Power stick and how it can unleash amazing power in even the weakest of people.