PURPOSE: To facilitate fender replacement by projecting the upper part of a side plating outboard to produce a turned square U shape expander from the center of a ship and connecting the fender to the outside of a projection pierced and bolted with bolts and nuts.

CONSTITUTION: An FRP shape 11 permits an upper part of a side plating to be projected outboard so that turned square U shape may be produced and developed from the center of the ship. A fender 3 is fastened to the outside of the projection of a reinforcing member 12 with bolts 3 and nuts 32. Installation of a cover 4 to the turned square U shaped opening produces a closed space which is used as a buoyncy chamber. A new fender can be easily installed with the same bolts and nuts after removing a cover 4 and loosening the bolts 31 and nuts after removing a cover 4 and loosening the bolts 31 and nuts 32 when fender replacement is required.