·When the propeller rotates through the main engine of the vessel, a very low constant current(mV) is generated.(Any object generates electricity between a rotating body and a non-rotating body) This current(mV) causes a potential difference with the hull, which causes corrosion of the propeller and shaft.

· In addition, propellers and shafts are made of different metals than the hull, which provides a cause of corrosion due to the ionization tendency of dissimilar metals.And, if the minute constant current generated from the shaft flows into the shaft-based bearing system, it may damage the bearing system with the main engine. Shaft Grounding Device is the product to compensate for this problem. This product can be applied to all shaft sizes.