Attwood 90841 Large Vented Battery Box – Group 29, Black
Free returns on all eligible orders
You have 30 days to request a return. All sale items are final sale.
The Attwood 90841 is a large vented marine battery box designed to fit Group 29 and Group 31 batteries — the deep-cycle and dual-purpose batteries commonly used for house banks, trolling motors, and high-draw marine electrical systems. Built from acid-resistant polypropylene and compliant with ABYC standard E-10 and USCG Specification 183.420, it meets the same standards as the rest of the Attwood battery box range in a larger footprint.
Four enlarged cable openings (0.55" diameter) allow clean routing of heavy-gauge battery cables without tight bends, and large handles with rolled edges make the box manageable during installation despite the added size and weight of Group 29/31 batteries. Mounting hardware is included.
- Fits Group 29 and Group 31 batteries
- Vented design — allows hydrogen gas to escape safely during charging of flooded lead-acid batteries
- Four enlarged cable openings — 0.55" diameter for clean, unrestricted cable routing
- Large handles with rolled edges for carrying and positioning
- ABYC E-10 and USCG 183.420 compliant
- Acid-resistant polypropylene construction
- Mounting hardware included
- Black finish
Best Use Case: Designed for Group 29 and Group 31 deep-cycle or dual-purpose batteries used in house banks, trolling motor systems, or high-capacity marine electrical setups. The larger footprint and reinforced handles make it practical for the heavier batteries in these groups.
Parts Desk Insights: This is a vented box — correct for flooded lead-acid (wet cell) batteries that off-gas hydrogen during charging. If you are installing a sealed AGM or gel battery, a non-vented enclosure is more appropriate. Group 29 and Group 31 batteries are physically large and heavy — confirm your installation space before ordering. For smaller battery groups, see the Attwood 90651 Standard Vented Battery Box – Group 24/24M, the Attwood 90671 Power Guard Vented Battery Box – Group 27M, or the Attwood 90707 PowerGuard Pro Battery Box – Group 24/27.
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.