







⚓ Seal the deal with Sikaflex-291 — where speed meets marine-grade strength!
Sikaflex-291 is a professional-grade, fast-curing polyurethane marine adhesive and sealant designed for durable, elastic seals on boats. It bonds excellently to gelcoat, fiberglass, metal, and wood, resists fresh and seawater, and is NSF and USDA approved for safe use around potable water and incidental food contact. Ideal for above and below waterline applications, it offers a paintable, vibration-resistant finish trusted by boat builders and marine pros.















| ASIN | B01GPIXX5Y |
| Best Sellers Rank | #5,602 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #38 in Silicone Adhesives #49 in Adhesive Caulk #101 in Industrial Sealants |
| Brand | SIKA |
| Color | White |
| Date First Available | June 8, 2005 |
| Is Discontinued By Manufacturer | No |
| Item Form | Gel |
| Item Package Quantity | 1 |
| Item Volume | 10.1 Fluid Ounces |
| Item Weight | 10.6 ounces |
| Item model number | 90919 |
| Manufacturer | Sika USA |
| Material | 1-C polyurethane |
| Package Information | Cartridge |
| Product Dimensions | 11.5 x 2 x 11.5 inches |
| UPC | 033886005258 |
| Unit Count | 10.1 Fluid Ounces |
| Viscosity | Moderate |
| Viscosity Level | Medium |
| Water Resistance Level | Water Resistant |
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.
D**T
Silkaflex Boat, RV, General use.
This is really good RTV! I didn't know Silksflex existed until I had to change out a pair of jet drives on a Zodiac Hurricane. Silksflex RTV was the recommended by the OEM manufacturer. I use Silkaflex on Motorhomes, trucks and around my house. Very strong and flexible and seawater resistant.
A**H
Works great!
I forget why I bought this - car repair? - but it worked great!
J**.
Very good product
Works great , sealed my RV fresh water tanks equalizer hose .
R**R
Great product if you have humidity
Wonderful, grippy, but gooey to apply - super great adhesion - but absolutely need humidity such as East or West coast, near water, Great Lakes or humid Georgia. I live in Colorado and it is still gooey on my sailboat - called the company - they said need 50-60% humidity or it won't dry. Used in my bathtub and I had to leave hot steaming water in the tube twice and it adhered perfectly. Otherwise would be 5 stars in a humid climate. 2 stars for Colorado - but it's not chemical reaction for drying - it's reactive to humidity.
A**Y
Old stock or poor seal at factory
Lucky if you get a tube that isn’t half dried up. The reviews on this don’t lie I ordered 5 tubes and they are extremely difficult to pump out of the tube and three were half way dried up solid.
L**A
Would buy again
Great product..worked well..
J**H
Used for Schoolie Bus Build
Ordered this Caulk for a schoolie bus build. Used approximately 1/2 tube or less per window. After completely removing all windows, removing old sealant, and reinstalling. Be sure to wipe or wash it off your hands as soon as you get any on you. This stuff is very difficult to remove from your skin once it's dried.
J**Y
Expensive for what size. There are other silicones on the market to look into before purchasing Sika Sikaflex 201.
B**R
I bought this Sika 291 to repair an aluminum canoe. This marine urethane is basically the same thing that SportsPal sells in their repair kit. I haven't used it yet but based on other reviews it will be fine for the repair I set out to accomplish Regarding other reviewers stating they received out of date or wrong colour product, I ordered black and got black and the use by date was 9 months into the future (July 2025) beyond my purchase date Nov/2024.
W**L
As advertised look forward to using in the spring.
A**R
It has worked well but they sent me the wrong colour and hubby did not read it before opening it.
P**D
J'ai commandé 6 tubes de ce produit dans le blanc. Les tubes reçu étaient tous identifié comme blanc selon les étiquettes sur les tubes mais 1 seul était blanc. Les autres sont tous noir. Le produit semble tout de même être de qualité, j'ai utilisé le blanc pour des endroits visible mais je vais perdre les 5 autres tubes car ce n'est pas la bonne couleur.
Trustpilot
4 dagen geleden
2 dagen geleden