CMP CM55989Z Mercury/Mercruiser Alpha One Gimbal Housing Nut Zinc Anode

The CMP CM55989Z is a sacrificial zinc button anode designed to protect Mercury and Mercruiser Alpha One and Bravo One sterndrive systems from the damaging effects of galvanic corrosion in saltwater environments. This anode is for saltwater use only and is not recommended for freshwater applications.

How It Works:

Sacrificial anodes work by introducing a more reactive metal into the underwater electrical circuit formed when dissimilar metals are submerged together. The zinc anode gives up its electrons preferentially, corroding in place of your drive's more expensive aluminum and steel components.

Key Features:

• Material: High-purity zinc — engineered for maximum galvanic protection in saltwater
• Outer Diameter: 1.2 in (approx. 31 mm)
• Height: 1.2 in (approx. 30 mm)
• Thread: 1/2-13 UNC
• Attaches to the Alpha One gimbal housing's mounting bolts
• Button-style design for easy installation and replacement
• Replaces OEM and aftermarket part numbers: 55989, CM55989, 55989Z, C55989, CAM-55989, 710-55989Q9, 710-55989Q, BSMM55989

Saltwater Use Only: Zinc anodes are specifically formulated for saltwater and brackish water environments. For freshwater use, magnesium anodes are recommended. For universal saltwater/freshwater protection, consider aluminum alternatives.

Inspect your anodes regularly and replace when more than 50% depleted to ensure continuous protection for your Mercury or Mercruiser sterndrive investment.