---
product_id: 12921025
title: "Martyr Anodes, CMR03, Zinc Rudder & Trim Tab Disc Anode with Stainless Steel Allen Head (0.5 H x 3.75 OD x 0.34 ID) – Marine Boat Sacrificial Anode for Saltwater Corrosion Protection"
brand: "martyr"
price: "404 kr"
currency: DKK
in_stock: true
url: https://www.desertcart.dk/products/12921025-martyr-anodes-cmr03-zinc-rudder-and-trim-tab-disc-anode
store_origin: DK
region: Denmark
---

# Zinc alloy for superior saltwater protection Precision stainless steel Allen head design ISO 9001 certified quality assurance Martyr Anodes, CMR03, Zinc Rudder & Trim Tab Disc Anode with Stainless Steel Allen Head (0.5 H x 3.75 OD x 0.34 ID) – Marine Boat Sacrificial Anode for Saltwater Corrosion Protection

**Brand:** martyr
**Price:** 404 kr
**Availability:** ✅ In Stock

## Summary

> 🛥️ Protect your ride, own the tide!

## Quick Answers

- **What is this?** Martyr Anodes, CMR03, Zinc Rudder & Trim Tab Disc Anode with Stainless Steel Allen Head (0.5 H x 3.75 OD x 0.34 ID) – Marine Boat Sacrificial Anode for Saltwater Corrosion Protection by martyr
- **How much does it cost?** 404 kr with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.dk](https://www.desertcart.dk/products/12921025-martyr-anodes-cmr03-zinc-rudder-and-trim-tab-disc-anode)

## Best For

- martyr enthusiasts

## Why This Product

- Trusted martyr brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Compact Yet Mighty:** Sized perfectly at 0.5 H x 3.75 OD x 0.34 inches to fit seamlessly on rudder and trim tabs, delivering maximum protection in minimal space.
- • **Effortless Installation:** Stainless steel Allen head and slotted drive system designed for quick, secure mounting—no hassle, no downtime.
- • **Ultimate Saltwater Defense:** Zinc alloy engineered to resist corrosion in harsh marine environments, keeping your vessel safe and sound.
- • **Certified Quality, Zero Compromise:** Manufactured under strict ISO 9001 standards to ensure peak performance and durability every time.
- • **Cost-Effective Cathodic Protection:** Protects iron, steel, aluminum, and magnesium components without breaking the bank—smart maintenance for savvy boaters.

## Overview

Martyr Anodes CMR03 is a premium zinc alloy anode designed for saltwater use, providing reliable cathodic protection for marine vessels. Manufactured with ISO 9001 quality standards and featuring a stainless steel Allen head for easy installation, this compact anode safeguards metal components like iron, steel, aluminum, and magnesium from corrosion, ensuring longevity and performance in demanding ocean environments.

## Description

Full description not available

## Features

- Zinc alloy for use in saltwater
- Martyr Anodes offer maximum protection by maintaining quality alloys, free from impurities like iron, which can compromise performance
- Provides low cost cathodic protection of ocean-going vessels, structures and equipment constructed of iron, steel, aluminum, magnesium, and other metals
- High-quality Martyr anodes are pressure diecast and manufactured to strict quality standards through an ISO 9001 Quality Management System
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## Technical Specifications

| Specification | Value |
|---------------|-------|
| Material | Zinc |
| Drive System | Slotted |
| Head Style | Trim |
| Exterior Finish | Aluminum,Stainless Steel,Steel,Zinc |
| Thread Size | Unthreaded |
| Point Style | Hex |
| Metal Type | Zinc |
| Brand | Martyr Anodes |
| Color | magnesium |
| Head Type | Hex |
| Item Weight | 0.72 Kilograms |
| Thread Type | Standard |
| Thread Coverage | Partially Threaded |
| Thread Style | Right Hand |
| Thread Class | 2A |
| Fastener Size | .5 inches |
| Size | .5 H x 3.75 OD x .34 |
| Item Diameter | 0.5 Inches |
| Compatible groove diameter | 2 Inches |
| Number of Pieces | 1 |
| UPC | 628309103545 |
| Global Trade Identification Number | 00628309103545 |
| Item Package Dimensions L x W x H | 9.29 x 6.54 x 2.32 inches |
| Package Weight | 0.74 Kilograms |
| Item Dimensions  LxWxH | 3.9 x 3.8 x 1.6 inches |
| Brand Name | Martyr Anodes |
| Number of Items | 1 |
| Manufacturer | Martyr |
| Part Number | CMR03 |
| Style | Zinc |
| Sport Type | Boating |

## Product Details

- **Material:** Zinc
- **Head Style:** Trim
- **Item dimensions L x W x H:** 3.9 x 3.8 x 1.6 inches
- **Exterior Finish:** Aluminum,Stainless Steel,Steel,Zinc
- **Thread Size:** Unthreaded

## Images

![Martyr Anodes, CMR03, Zinc Rudder & Trim Tab Disc Anode with Stainless Steel Allen Head (0.5 H x 3.75 OD x 0.34 ID) – Marine Boat Sacrificial Anode for Saltwater Corrosion Protection - Image 1](https://m.media-amazon.com/images/I/81OdKriMNQL.jpg)

## Available Options

This product comes in different **Size** options.

## Questions & Answers

**Q: Is this a pancake anode? Does it have the top and the bottom anode?**
A: I ordered two not being sure what the configuration was.  These are pancake anodes - flat on one side and domed on the other.  They apparently come in pairs where a QTY of 1 gets you two anodes connected together with a screw that can be easily separated to expose the flat side.  I received two pairs with a QTY of 2.

**Q: The listing says this is for a cmr 5, but the picture shows a cmr 3.  which is it?**
A: It is a CMR5. It is 5" in diameter and 3/4" thick. I put them on my Bennett trim tabs, replacing the old original factory anodes. Fit perfectly.

**Q: Will this work to prevent galvanic corrosion between steel and aluminum that is not in the water?**
A: I don’t believe it will

**Q: How many pieces come with an order, 2?**
A: Yes. 2.

## Frequently Bought Together

- Martyr CMR Rudder/Trim Tab Anodes
- Martyr Anodes, Streamlined Shaft Anodes with Stainless Steel Slotted Head
- Martyr CMDIVERA, Aluminum Alloy Pleasurecraft Divers Dream Slotted Bolt-on

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**Shop now:** [https://www.desertcart.dk/products/12921025-martyr-anodes-cmr03-zinc-rudder-and-trim-tab-disc-anode](https://www.desertcart.dk/products/12921025-martyr-anodes-cmr03-zinc-rudder-and-trim-tab-disc-anode)

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*Product available on Desertcart Denmark*
*Store origin: DK*
*Last updated: 2026-02-21*