3M 4000UV Fast Cure Marine Sealant – White, 10 oz. Cartridge
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You have 30 days to request a return. All sale items are final sale.
3M 4000UV Fast Cure Marine Sealant – White, 10 oz. Cartridge
3M 4000UV is a one-part polyurethane marine sealant engineered for speed and UV durability. It tacks off in under 2 hours and fully cures in 24 hours — significantly faster than standard 5200 — while delivering a firm, rubbery, watertight seal that flexes with the boat through shock, vibration, and seasonal movement. The built-in UV inhibitors keep the white finish bright and resist surface degradation over time. The 10 oz. cartridge format is ideal for larger installations and production work.
Key Features
- Fast cure: tack-free in under 2 hours, fully cured in 24 hours
- Superior UV resistance — white finish stays bright without yellowing
- Firm, rubbery seal that flexes with shock, vibration, and thermal movement
- One-part formula — no mixing required
- Suitable for use above and below the waterline
- 10 oz. cartridge — requires a standard caulking gun
Compatible Applications
- Deck hardware bedding where a fast return-to-service time is needed
- Port lights, hatches, and windshield frame sealing
- Hull-to-deck joints and above-waterline structural seams
- Fiberglass, wood, metal, and painted surface bonding
- Any marine sealing application requiring strong UV resistance
Parts Desk Insights
Best Use Case: 3M 4000UV is the sweet spot between the permanent aggression of 5200 and the softer hold of silicone — it cures fast, holds firmly, and resists UV better than standard polyurethane. It’s the preferred choice for deck hardware, port lights, and above-waterline seams where you want a strong bond but may need to revisit the fitting in a few seasons. For smaller touch-up jobs without a caulking gun, see the 3M 4000UV Fast Cure Sealant – White, 3 oz. Tube (05280). When a truly permanent structural bond is required (hull-to-deck, keel bolts, through-hulls), 3M 5200 Marine Sealant is the stronger choice. For finishing the bead after application, the Star Brite Caulk Rite Finishing Tool delivers a clean, professional edge.
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.