Marine-grade urethane fully encapsulates Riptide control boards to protect the electronic circuitry. All electrical connections are sealed with waterproof heat-shrink tubing to keep saltwater out. We use metals that are properly balanced & a composite shaft to ward off galvanic corrosion. So the only piece left for saltwater to attack is this little zinc anode, which absorbs corrosion so the rest of the motor doesn't have to. Indestructible Composite Shaft: Pound for pound, our composite shaft is stronger than steel.