Tecnoseal Zinc Yamaha Trim Tab Anode f/150 - 225 HP MotorsZinc Yamaha Trim Tab Anode for 150 225 HP Motors A trim tab anode helps counteract the torque that a propeller creates, and levels out "prop walk," which is a propeller's tendency to rotate concerning a vertical axis. Also, trim tab anodes can absorb various types of corrosion, helping alleviate corrosion to other parts of the boat. Features: Designed for 150 225 HP Yamaha motors Meant for saltwater boat use Boat type: Motorboat with outboard