Aluminum Rudder Anode 3-3/4" CMT-R03AL
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You have 30 days to request a return. All sale items are final sale.
The CMT-R03AL is a 3-3/4" aluminum rudder anode (R-3 style) designed to protect rudders and trim tabs from galvanic corrosion. This compact clamshell-style anode mounts securely around the rudder, sacrificing itself to protect critical underwater metals.
Manufactured from marine-grade aluminum alloy, it provides longer-lasting protection than zinc and performs reliably in saltwater, brackish, and freshwater environments.
Key Features
- 3-3/4" diameter rudder/trim tab anode
- Marine-grade aluminum alloy (multi-water compatible)
- Two-piece clamshell design with stainless hardware
- Longer lifespan vs zinc
- Full surface contact for effective protection
- Easy bolt-on installation
Application / Compatibility
Designed for:
- Rudders
- Trim tabs
- Smaller underwater surfaces
✔ Common on:
- Inboard boats
- Smaller cruisers and sailboats
- Compact rudder systems
✔ Protects:
- Rudder plates
- Trim tabs
- Adjacent bonded metals
Serial Number Fitment Notice
Always confirm:
- Diameter (3-3/4")
- Thickness (~5/8"–3/4")
- Mounting hole size and spacing
Proper fit ensures correct contact and corrosion protection.
When This Part Needs Replacement
- Anode is 50% or more consumed
- Uneven wear or pitting
- Loss of thickness
- Routine haul-out inspection
Installation Notes
- Install on clean, bare metal surface
- Tighten evenly across both halves
- Do not paint the anode
- Inspect mounting hardware regularly
- Replace before full depletion
Alternate / Superseded Part Numbers
- Camp Company: CMT-R03AL
- Martyr: CMR03AL
- Zinc version: CMT-R03Z
- Magnesium version available for freshwater
Parts Desk Insight
The R-3 size is ideal for smaller rudders and trim tabs where space is limited. Aluminum is the better choice for mixed water use—it won’t lose effectiveness like zinc in brackish conditions.
Shipping
Shipping: Ships same or next day for fast Canada wide shipping. ⚓
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 3–4 business days.
Special-order items: timeline confirmed after order.
Returns & warranty
Returns & Satisfaction Guarantee
We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.
If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.
To qualify for a return:
Item must be in new, unused condition
Product must be in its original packaging
All parts, components, hardware, manuals, and accessories must be included
Packaging must be undamaged and suitable for resale
Important:
Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.
We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.
For return authorization, please contact our support team before shipping anything back.