designer's own words:Every year, surfers get seriously injured or killed by the attack of sharks. The coast guard keeps watch on for their safety, but as long as it's unknowable that when, from where sharks may showup, keeping surfers 100% free form sharks' attack is impossible. Hereupon, I suggest a design of self-generated surfboard capable of protecting surfers safety from sharks. protecting board is hydraulic power using charger. Previous ones were short in time of current emission and its range was limited. But, protecting board is the method to gather at underneath the board the energy from the motor turning by hydraulic power, which will emit 1.5 volt current around the board while surfing. Sharks make a sharp distinction between their preys and opponents bigger then themselves by sensing micro current through 'Lorenzini Organ' hundreds of micro holes near nose. The I.5 vole current emitted from P&B is about 3000 times stronger than that from fishes making sharks believe they have met opponents stronger than themselves and run away. Thus gathered energy protects the surfers from sharks while enjoining surfing.