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Martyr Anodes CM31640A Trim Tab Anode for Mercury Mercruiser

Manufacturer

Martyr Anodes

<h3>About Martyr Anodes</h3><p>When it comes to defending a vessel against galvanic corrosion, few names carry the authority of <strong>Martyr Anodes</strong>. A flagship brand within the <strong>CMP Group</strong>, Martyr has its roots in foundry operations that date back to the early 1900s in Vancouver, BC, growing from a local manufacturer into a globally recognized leader in marine cathodic protection. Today, the brand supplies boaters, commercial operators, and marine professionals worldwide with sacrificial anodes engineered to guard hulls, propellers, rudders, shafts, engines, and other submerged components from the relentless effects of corrosion.</p><h3>Three Alloys, Every Water Type</h3><p>What sets Martyr apart from competing anode manufacturers is its position as the only brand to offer all three protective alloys — zinc, aluminum, and magnesium — under a single product line. This matters because the correct alloy depends entirely on the water environment a vessel operates in. Zinc anodes are the classic choice for aggressive saltwater conditions, while aluminum anodes are preferred for saltwater and brackish environments, offering superior corrosion resistance with a reduced environmental footprint. Magnesium anodes are the go-to solution for freshwater use, delivering effective sacrificial protection without degrading too quickly. Whatever the operating environment, Martyr has an engineered solution to match.</p><h3>Military-Grade Manufacturing Standards</h3><p>Martyr does not cut corners on metallurgy. Every anode is pressure die-cast and manufactured to meet or exceed <strong>U.S. Military alloy specifications</strong>, using only high-purity metals. Each alloy batch is lab-tested with full certification and traceability available upon request. This rigorous quality management — operating under an ISO 9001 framework — ensures that each anode delivers consistent, long-lasting galvanic performance across a wide range of marine environments, from recreational pleasure craft to commercial vessels and naval applications.</p><h3>Anode Kits for Simplified Protection</h3><p>For boaters who want a complete, hassle-free maintenance solution, Martyr&rsquo;s <a href="/7452-martyr-anodes-anode-kits-200102">Anode Kits</a> offer pre-packaged sets engineered for specific engine models and boat types. Compatible with major marine engine brands including Yamaha, Mercury, Volvo, and MerCruiser, these kits take the guesswork out of corrosion protection and ensure every critical system receives optimal coverage in a single purchase.</p><h3>Sustainability at the Core</h3><p>Martyr and the CMP Group have made environmental stewardship a cornerstone of their mission. Traditional zinc anodes can contain cadmium, a metal that poses risks to aquatic ecosystems. Martyr actively advocates for the adoption of aluminum and magnesium alternatives that deliver equal or superior protection while minimizing harm to marine environments — embodying the brand&rsquo;s philosophy of &ldquo;Protect your boat, protect our waters.&rdquo; With over 1,000 anode types available and a catalog that fits virtually every major marine engine and boat model, Martyr remains one of the most comprehensive and trusted sources for marine corrosion protection in the world.</p>

Part Number

CM31640A
06/03/2036 8:36 AM
Sale Price

$8.42

In Stock (10+)

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Usually delivered within 2 days

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No Hassle Returns

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Fitment guaranteed

Fitment guaranteed

Product Details

The Martyr Anodes CM31640A is a high-quality aluminum sacrificial anode designed specifically for Mercury and Mercruiser stern drive and outboard applications. This trim tab anode provides essential corrosion protection for your drive unit by sacrificing itself to prevent galvanic corrosion on more expensive metal components.

Key Features:

  • Manufactured from high-grade aluminum alloy for optimal protection in saltwater and brackish water environments
  • Precision-engineered to meet or exceed OEM specifications for Mercury Mercruiser drives
  • Direct replacement for Mercury part number 31640
  • Mounts to the trim tab on the lower unit of the stern drive
  • Provides reliable galvanic corrosion protection for underwater metal components
  • Easy installation with proper hardware included

Sacrificial anodes are a critical component of your marine corrosion protection system and should be inspected regularly and replaced when 50% depleted. Always verify propeller clearance after installing new trim tab anodes to ensure proper fitment and safe operation.

Products specifications

Description

Standard Trim Tab, Fits GEN. II

Material

Aluminum

looks like what I need

Always great to do business with

Very satisfied. Will definitely shop here again in the future when the need arises.

Quick, Easy, and Most Economical Found Online!

Quick and Easy with the best prices by far.

Quick service

ugg... the description was lacking

Fast connection with Amazon

Found what I needed for a good price. They Forgot to send my shipping info but my order still arrived on time so it was no big deal.

Best price i could find anywhere. Lightning fast shipping.

fast checkout

Everything was great just the returning could use help. The first ine i ordered was wrong and shipping back to you is more costly than i hoped.

First time buyer from Autoplicity and found the website easy to navigate and find what I wanted quickly. They had the best price of all the other sites I checked, including shipping.

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