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Martyr Anodes CM875821Z Volvo Penta Duo Prop Ring Anode Zinc

Manufacturer

Martyr Anodes

<h3>Martyr Anodes: The World&apos;s Premium Marine Corrosion Protection</h3><p>Few threats to a vessel are as silent and relentless as galvanic corrosion. Submerged metal components—propellers, rudders, shafts, trim tabs, and engine parts—are constantly at risk when dissimilar metals come into contact in an electrolytic environment like seawater. <strong>Martyr Anodes</strong> has spent decades engineering sacrificial anodes specifically to stop that process in its tracks, earning a reputation as one of the most trusted names in marine cathodic protection worldwide.</p><p>Operating as a flagship brand within the CMP Group, Martyr holds a unique distinction in the industry: <a href="/7452-martyr-anodes-anodeszincs-200103">it is the only manufacturer to offer all three anode alloys</a>—zinc, aluminum, and magnesium—under one roof. That breadth matters because the optimal anode material depends entirely on the water you sail. Zinc is the traditional choice for saltwater applications, aluminum excels in saltwater and brackish conditions while delivering a reduced environmental footprint, and magnesium is the go-to solution for freshwater boaters. Having all three alloys available means every boater can select the right protection for their specific environment.</p><h3>Military-Grade Standards, Lab-Certified Quality</h3><p>Quality at Martyr is not a marketing claim—it is a specification. Every anode in the lineup is pressure die-cast and manufactured to strict U.S. Military Alloy Specifications, including MIL-DTL-18001 for zinc and MIL-DTL-24779C for aluminum. Each alloy batch undergoes laboratory testing with full certification and traceability available upon request. The result is an anode with consistent electrochemical activity, even consumption rates, and predictable service life—qualities that professional mariners and weekend boaters alike can depend on season after season.</p><p>With <a href="/7452-martyr-anodes-anodeszincs-200103">more than 1,000 individual anode types</a> covering hulls, shafts, propellers, rudders, trim tabs, bow thrusters, and outboard engines, the Martyr catalog is engineered to fit virtually every major marine engine brand and boat model. Compatibility is a priority: the anodes are designed to precise industry standards for weight and dimension so they drop into place without guesswork.</p><h3>Simplified Protection with Anode Kits</h3><p>For boaters who want a straightforward path to complete corrosion coverage, Martyr&apos;s <a href="/7452-martyr-anodes-anode-kits-200102">engine-specific anode kits</a> deliver everything needed for a full service in a single package. Each kit is assembled for a specific engine make, model, horsepower range, and water type, eliminating the need to source individual pieces separately. Kits are available for top engine brands including Yamaha, Mercury, Volvo, and MerCruiser—making seasonal anode replacement a fast, confident job at the dock or in the yard.</p><h3>A Commitment to Sustainable Boating</h3><p>Martyr has also taken a leadership role on the environmental side of corrosion protection. Traditional zinc anodes can contain cadmium, a metal that poses risks to aquatic ecosystems. As part of its broader corrosion control mission, Martyr has actively championed the adoption of aluminum and magnesium anodes as safer, more sustainable alternatives—materials that deliver equal or superior cathodic performance without the ecological concerns associated with cadmium-containing zinc. That philosophy reflects a brand whose protection ethos extends from the boat to the water around it.</p><p>Whether you are fitting out a new vessel, performing routine seasonal maintenance, or upgrading an aging protection system, Martyr Anodes offers a complete, verified solution backed by rigorous engineering and a century-long heritage of foundry expertise.</p>

Part Number

CM875821Z
09/13/2036 7:56 AM
Sale Price

$19.24

In Stock (10+)

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Usually delivered within 2 days

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No Hassle Returns

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Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Martyr Anodes CM875821Z is a precision-engineered zinc ring anode designed specifically for Volvo Penta duo prop drive systems. This sacrificial anode provides critical corrosion protection for your sterndrive components in saltwater and brackish water environments.

Key Features:

  • Direct replacement for Volvo Penta part number 875821
  • Zinc alloy composition optimized for saltwater protection
  • Ring design fits duo prop propeller systems
  • Prevents galvanic corrosion on expensive drive components
  • Meets or exceeds OEM specifications

Martyr is the industry leader in sacrificial anode technology, manufacturing anodes to strict military specifications. Regular inspection and replacement of this anode helps extend the life of your Volvo Penta sterndrive and prevent costly corrosion damage to propellers, shafts, and drive housings.

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