leakage gasket 746 placed between the flange 743 is bored with a plurality of holes 747 for screws to pass through to assemble the transmitting unit 7 with the board body 1 the fan unit 75 has a plurality of fans 751 positioned to hide inside the cylinder 742 and is connected with the shaft of the motor 723 extending through the cone 741 and reaching the inside of the cylinder 742 the anti pollution net unit consists of a circular net 761 capped on the rear opening of the cylinder 742 and a plurality of quadrilateral nets 762 capped on the openings 744 preventing dirty matters in sea water from going into the cylinder 742 to bump or smear the fans 751 in using this board referring fig4 a user lies on it with his face down and his upper body touching the recessed lying portion 12 and grips the left and the right grip 31 and 32 with his hands operating the rotatable button 322 to control the propelling speed generated by the motor unit 72 permitting the body 1 to move forward on water then water can flow in through the current guider 4 then flowing through a plurality of holes 413 bored in the rear portion sides of the protective housing 41 and finally through the quadrilateral nets 762 capped on the openings 744 in the current sucker 74 so that the fan unit 75 may rotate at a great speed to suck the water current generating propelling power to push forward the body 1 therefore the water current coming from the forward direction can alleviate the power consumption of the motor 723 for rotating the fan unit 75 when a user wants to change the moving.