NOCO HM408 Commercial-Grade Battery Box – Single 4D, Rotationally Molded
Free returns on all eligible orders
You have 30 days to request a return. All sale items are final sale.
NOCO HM408 Commercial-Grade Battery Box – Single 4D
Built for demanding marine, RV, and commercial applications, the HM408 is a heavy-duty enclosure designed to house a single Group 4D battery in environments where standard battery boxes simply aren’t enough. The rotationally molded construction delivers exceptional impact resistance and structural rigidity, protecting your battery against UV exposure, oil, fuel, and other contaminants season after season.
A four-corner fastening system and captive lid keep the box securely closed even in rough conditions, while large cable entry holes accepting up to 4/0 AWG wire make it compatible with high-current applications and heavy-gauge wiring runs. Full-flow ventilation channels safely release battery gases, and a built-in battery acid reservoir provides an added layer of protection against spills.
Meets USCG CFR 183.420 and ABYC E-10.7 standards — a compliant choice for inspected vessels and commercial workboats.
Key Features
- Rotationally molded construction for superior impact resistance and UV protection
- Four-corner fastening system with captive lid
- Large cable entry holes — accepts up to 4/0 AWG wire
- Full-flow ventilation for safe battery gas release
- Built-in battery acid reservoir
- Meets USCG CFR 183.420 and ABYC E-10.7 standards
- Fits single Group 4D batteries
- Suitable for marine, RV, and commercial equipment
Best Use Case
The go-to enclosure for commercial workboats, large offshore fishing vessels, and heavy-duty RV or generator installations running a single Group 4D battery. The rotationally molded shell and compliance certifications make it the right choice when a standard snap-top or injection-molded box won’t meet the structural or regulatory requirements of the application. Particularly well-suited for engine rooms and bilge compartments where chemical exposure, vibration, and temperature extremes are a concern.
Parts Desk Insights
The HM408 is part of NOCO’s commercial-grade HM series. If your installation requires a different battery configuration, see the NOCO HM484 Commercial-Grade Battery Box – Single 8D for a larger single-battery option, the NOCO HM426 Commercial-Grade Battery Box – Dual 6V for dual 6V configurations, or the NOCO HM485 Commercial-Grade Battery Box – Dual 8D for the largest dual-battery option in the series. For smaller Group 24–31 applications, see the NOCO BG31 Snap Top Battery Box – Group 24–31 or the NOCO BG27 Snap Top Battery Box – Group 27.
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.