







🖤 Seal it strong, seal it smart — the pro’s choice for lasting bonds!
Sikaflex 221 is a professional-grade, multi-purpose polyurethane adhesive and sealant offering a 45-minute open time and permanent elasticity. It bonds strongly to diverse materials including metal, plastic, and ceramics, cures waterproof and flexible, and can be sanded and painted for a flawless finish. Ideal for demanding automotive, marine, and construction applications where durability and precision matter.

























| ASIN | B00DUX6PY4 |
| Best Sellers Rank | 2,056 in DIY & Tools ( See Top 100 in DIY & Tools ) 50 in Sealers |
| Brand | Sika |
| Colour | Black |
| Compatible Material | Metal, Porcelain |
| Country Of Origin | Switzerland |
| Customer Reviews | 4.6 4.6 out of 5 stars (622) |
| Global Trade Identification Number | 04003923245776 |
| Included Components | 1x Cartridge |
| Item Dimensions | 50 x 50 x 230 millimetres |
| Item Form | Paste |
| Item Type Name | Sealant and Adhesive |
| Item Weight | 0.45 Grams |
| Manufacturer | Sika Everbuild |
| Manufacturer Contact Information | Sika Everbuild 41 Knowsthorpe Way, Leeds LS9 0SW |
| Manufacturer Part Number | SIKAFLEX221/40 |
| Material | Polyurethane |
| Model Number | 221 |
| Number of Items | 1 |
| Style Name | Compact |
| Surface Recommendation | Window |
| Unit Count | 300.0 millilitre(s) |
| Water Resistance Level | Waterproof |
C**L
Extremely Strong Adhesion, Professional Quality
This is not comparable to standard DIY sealants you might find in typical hardware stores. I’ve used Sikaflex 221 several times over the past year for various automotive and general fixing jobs, and the performance is far superior to basic alternatives. The adhesive strength is excellent. Once applied, it bonds very firmly and creates a durable, flexible seal. It works well on multiple surfaces including metal and plastic, making it ideal for vehicle modifications and exterior applications. It’s especially useful where a strong, permanent bond is required. After curing, it remains slightly flexible, which helps prevent cracking due to vibration or movement. One important thing to be aware of is how sticky it is. If it gets on your hands, tools, or unintended surfaces, it can be difficult to remove. Careful application and preparation are essential. Pros: • Extremely strong adhesion • Professional-grade quality • Works on multiple surfaces • Flexible once cured • Ideal for automotive and outdoor use Cons: • Difficult to remove if applied accidentally • Requires careful handling during application Overall: A high-quality adhesive and sealant that provides excellent strength and durability. Ideal for automotive, DIY, and permanent bonding applications where reliability is important.
B**R
Professional grade product at reasonable prices
Sika products are seriously good products, expensive but worth every penny. I used this to bond 12mm marine ply to line the tops of the doors on my van , use disposable gloves because it will tack and stick to pretty much everything…. Its leak prevention is excellent, easy to use and very effective. Be warned though it sticks to everything so be careful you don’t get it on anything you don’t want it on because it’s almost impossible to remove easily. Sika make a lot of very specific products so do a little research first to find the exact product for your particular task …… you will be surprised at what they actually provide. This is professional grade products, very strong and can be used as a sealer as well as an adhesive. I found that if you wrap up the tube after use and seal it I can actually get a few days use out of the tube before it finally hardens..
M**.
👍
Very good and strong
D**N
Good quality adhesive/mastic
I used this to bond and seal a rear window into an old Land Rover. Easy to apply with a mastic gun.
P**Y
strong sticky and long lasting
This is advertised as a strong adhesive sealant and that's exactly what it is. I first used this for work as an adhesive to stick woven polyethylene slabs to an outer polypropylene shell. Both plastics had to be surface activated but after that the sikaflex stuck them so tight they couldn't be pulled apart. I've since used it to stick door seals to my Land Rover and to seal a leak in the roof. This is fantastic stuff, I've now always got some for those jobs where I don't trust ordinary sealant. The only downside is that it doesn't last very long (goes off in the tube) once opened compared to ordinary bathroom silicone. A note of warning- don't use this if you anticipate wanting to undo the thing quite soon.
U**N
Strong and good quality
used to joint my spoiler onto a Tiguan, works perfectly and still on very solid
A**R
SilkaGenius
Super sticky. Top stuff
P**.
Does the job very well
Does the job very well
Trustpilot
3 days ago
3 weeks ago