⚓ Seal the deal with speed and strength—your boat’s best kept secret!
Sikaflex-291 is a fast-curing, polyurethane marine adhesive and sealant designed for professional use. It bonds securely to gelcoat, fiberglass, metal, and wood, offering superior resistance to water, chemicals, and oils. Approved for potable water and incidental food contact, it performs reliably above and below the waterline, making it the go-to choice for boat builders who demand speed, durability, and safety.
J**F
Holds well, good gap filler.
Used this to fill the seam between the hull and deck. Used an electric calking gun allowing for controlled flow into the seams which were 22ft runs from stern to bow. took two tubes of Silkaflex. While fresh it was easy to use a scraper to push this material deeper into the seam and simple to remove excess leaving a smooth seam level with the deck. It took several days to harden to my satisfaction and in the meantime collected a layer of dust onto its surface. Once painted there is a subtle but clear discoloration showing through the paint. It's a good product but as this was a restoration job on a classic wooden boat I think epoxy would have been a better choice. But, no complaints with how this material works and I'm sure it will hold up for some time as the hull and deck flex a bit with movement and with the natural swelling and shrinking inherent in wood.
R**H
Better than what you get at lowes or homedepot
Ordered multiple tube's only one came the wrong color. I sealed the cracks in a torched hardwood floor and it's beautiful. Perfect and sands smooth
D**N
opinion
good product for general sealing of joints.
A**N
A Polyurethane sealant that allows removal of fittings if needed.
My go to marine sealant for deck fittings and strakes on all my scratch built boats.
K**.
Bought white but came black
Well it pays to pay attention. Bought a tube in October and finally getting around to using it today, Jan 30. Hurricanes slowed me down. Took all the old caulk out of the funnels, taped it off and went to start to re-caulk and lo and behold it’s black! The label pictured does say white but after looking at the tube itself near the label does say black. Now I’ve had to reorder and pay the expedited shipping since it took me 2 hours to tape off the gunnels not to mention the time it took to remove the old stuff and don’t want to leave tape on the fiberglass in the sun to long. Way to go Amazon and Sika!
M**R
Strong
Worked well, though it dries a bit off white
L**E
The best marine caulk on the market!
I've purchased so many tubes of this, because it's just so great. I'm working on a campervan conversion and this is the only sealant I use to cover up holes and leaks on the body.
J**N
#1
They don't make a better quality sealant
Trustpilot
2 days ago
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