SEACHOICE magnesium anode kit for Mercruiser Alpha One Gen II, One Size Magnesium — freshwater protection, cadmium-free

Seachoice’s magnesium anode kit protects Mercruiser Alpha One Gen II outboards (1991 and newer) from galvanic corrosion in freshwater environments.

If you own a Mercruiser Alpha One Gen II outboard and boat in lakes or rivers, this complete SEACHOICE anode kit supplies all the sacrificial parts needed to slow electrolytic wear. The set is made of magnesium for superior performance in fresh water, avoids cadmium for environmental safety, and meets Mil-Spec A-21412(SH) standards. It replaces the key zinc or sacrificial parts around the gimbal housing, ventilation plate, trim rams and prop-to-gear-housing junction so you can maintain effective corrosion control season after season.

What exactly is included in the kit and how does each part function?

This kit bundles every anode element used on the Alpha One Gen II lower unit to create a balanced sacrificial system. Each component is shaped to protect a specific metal surface so the magnesium corrodes first, preserving expensive gear housings and fasteners.

• 1 block anode for the gimbal housing — guards the bellows and housing junction
• 1 anode plate for the top of the ventilation plate — protects the ventilation plate surface
• 1 skeg anode for the ventilation plate — shields the skeg area from stray current
• 2 collar anodes for trim rams — prevent pitting on the hydraulic rams
• 1 prop/gear-housing collar anode — defends the shaft area between prop and housing
• 18 stainless steel 8/304 screws — hardware supplied for secure, long-lasting installation

How do I know this kit fits my Mercruiser Alpha One Gen II outboard?

The kit is engineered specifically for Alpha One Gen II models from 1991 onward; the shapes, sizes and screw count match OEM locations. Confirm compatibility by checking your lower unit type and model year against the kit’s application before purchasing.

• Made for Mercury/Mariner Alpha One Gen II outboards (1991 & newer)
• Includes the exact anode shapes used on the Gen II ventilation plate and gimbal areas
• Part number: 50-95031 — use this to verify fit with your service manual or dealer

Why choose magnesium and cadmium-free anodes for freshwater use?

Magnesium anodes are more electrochemically active than zinc in low-salinity water, so they offer faster and more effective protection on lakes and rivers. This kit avoids cadmium—reducing environmental toxicity—while still meeting military specification standards for material and performance.

• Magnesium composition optimizes sacrificial protection in fresh water
• Cadmium-free to reduce environmental impact and regulatory concerns
• Conforms to Mil-Spec A-21412(SH) for consistent material quality

What is involved in installing and maintaining these anodes?

Installation is straightforward for a competent DIY boater or mechanic: remove the worn anodes, fasten the new pieces using the included 8/304 stainless screws, and torque to manufacturer recommendations. Inspect anodes at least once per season and replace when they've lost most of their original mass or the profile is excessively eroded.

• Includes 18 stainless screws for secure, corrosion-resistant mounting
• Replace anodes when more than half-consumed or unevenly corroded
• Follow boat manufacturer torque specs and service intervals for best results

Who is this for: This SEACHOICE magnesium anode kit is aimed at freshwater boat owners, marine technicians and DIYers with Mercruiser Alpha One Gen II outboards (1991 and newer) who want a complete, environmentally-conscious sacrificial protection set. It’s also suitable for marinas and service shops that prefer cadmium-free components and Mil-Spec conformity when servicing multiple Alpha One Gen II engines.