Zinc Pencil Anode 3/8" NPT x 1/2" x 2" – CMT-E1
Free returns on all eligible orders
You have 30 days to request a return. All sale items are final sale.
Martyr CMT-E1 is a zinc pencil anode sized 3/8" NPT x 1/2" x 2", used to help protect marine engine cooling passages, heat exchangers, and related internal water-side components from galvanic corrosion in saltwater service. This is a pencil-style engine anode with brass plug. Zinc is intended for saltwater use.
Key Features
- Zinc pencil anode with brass plug
- Thread size: 3/8" NPT
- Anode diameter: 1/2"
- Anode length: 2"
- Designed for engine cooling system and heat exchanger corrosion protection
Engine Compatibility
This part is used across a range of marine engines, generators, coolers, and heat exchanger systems that take a 3/8" NPT pencil anode in the 1/2" x 2" size. Fitment should be confirmed by thread size, anode length, anode diameter, and the installed plug/anode style rather than by engine family alone.
Serial Number Fitment Notice
Fitment should be confirmed by cooling-system anode size and thread specification rather than serial number alone. Match the existing anode by 3/8" NPT plug thread, 1/2" anode diameter, and 2" anode length before ordering.
When This Part Needs Replacement
Replace when the zinc is heavily wasted, brittle, scaled, reduced in diameter, or no longer providing usable protective mass. Pencil anodes should be inspected regularly because they protect internal cooling passages where corrosion can become costly if service is delayed.
Installation Notes
Install only where a 3/8" NPT pencil anode of this exact size is specified. Remove the old anode carefully, inspect the plug threads and sealing surfaces, and confirm the replacement length does not interfere with the internal passage. Zinc is the correct material for saltwater applications; for other water conditions, material choice should be confirmed by application.
Alternate / Superseded Part Numbers
- CME1
- E-1
- CMT-E1
Parts Desk Insight
Pencil anodes are one of the simplest and most important maintenance items in raw-water cooling systems. Matching the thread is only part of the job—the anode diameter and length also need to match the housing so protection is correct and internal clearance is maintained.
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.