Attwood SL34405 Gas Spring 20" Extended, 12" Compressesd, 40 lbs.
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You have 30 days to request a return. All sale items are final sale.
Attwood SL34405 gas spring is a popular replacement for marine hatch/deck hatch lift support, offering an extended length of 20" and a compressed length of 12" with a 40 lbs force rating (SL34-40-5 / 23-SL34405).
Key Features
- Replacement marine gas spring for hatch/deck hatch applications
- 20" extended length; 12" compressed length (8" stroke)
- 40 lbs output force for controlled opening support
- Passes ASTM B117 salt spray testing plus Attwood salt spray and a 30,000-cycle lifecycle test
- Made with bio-degradable, no-hazard-to-water grade oil (WGK) for a more environmentally friendly gas-spring design
Intended Use
- Marine deck hatches and access ports
- Livewell and locker related hatch supports (as applicable to mounting style)
- General hatch lift-assist applications using Attwood/Ni-Slide style gas spring mounts
Product Details
- Brand/Series: Attwood SL34405 (also listed as SL34-40-5)
- SKU: 23-SL34405
- Mounting: Eyelet-style upper and lower mounts (8 mm rod / 10 mm socket)
- Dimensions: 20" extended; 12" compressed; 8" stroke
- Force: 40 lbs output force
- Lifecycle/testing: ASTM B117 salt spray; Attwood salt spray; 30,000 cycle lifecycle test
- Notes: Mounting brackets are available separately
Parts Desk Insights
Best Use Case: Best for restoring smooth, reliable lift support to marine hatches/deck access ports when the existing gas spring has weakened or stopped holding the lid reliably.
Common Issues: Common fitment causes are using the wrong stroke length or force rating, and mismatched mounting hardware (eyelet spacing/bracket style). If the hatch won’t stay up or feels weak, confirm the extended/compressed lengths and that the correct mounting brackets are being used for your hatch’s hardware setup.
Related Products & Accessories
- Mounting Brackets (sold separately) - This gas spring is intended to pair with the correct Attwood mounting brackets for your hatch/deck plate application.
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 1-3 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.