Can this be over sprayed with a clear lacquer to protect from discolouration or would the lacquer just peel off in time?

My answer to your question is no. Because of the way sikaflex works is that it doesn't dry totally so it remains flexible to take up movement. This leaves the seal intact and waterproof. Paint or lacquer will crack a fall off in my experience

can it be smoothed with soap water?

I've just used it to seal my lockers on our caravan. Used a mastic gun. I would not personally use soap to smooth it over. Once on its better than no more nails. But like I say I used it for our caravan.. Excellent stuff

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Sika Flex 521 UV, White, Polyurethane Hybrid Multi-Purpose Sealant, Adhesive Sealant for Sealing and Elastic Joints, Weatherproof, 300 ml

Product ID: 48284394

Details

Brand
Sika
Colour
Weiß
Full cure time
3E+1 Minutes
Item weight
0.42 Kilograms
Liquid volume
300

⚡High electrical resistance

🎨Paintable & sandable finish

🛡️Weatherproof & aging resistant

₱3404

Duties & taxes included

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Sold byAmazon PhilippinesDelivered byDesertcartCustomer service byDesertcartReturns14 days · 30 with PRO

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Description

🛠️ Seal smart, last longer — the pro’s choice for flawless finishes!

CUSTOM FINISH READY - Easily sanded and painted to blend perfectly with your project’s aesthetic.
FLEXIBLE DURABLE SEAL - Elastic formula maintains integrity under stress, ensuring long-lasting protection.
ECO CONSCIOUS SAFE FORMULA - Solvent, silicone, and PVC-free for a cleaner, professional-grade application.
ULTIMATE WEATHERPROOF SHIELD - Stay worry-free with superior resistance to aging and harsh weather conditions.
VERSATILE MULTI SURFACE ADHESION - Seamlessly bonds wood, metals, ceramics, plastics, and painted surfaces without special prep.

Sika Flex 521 UV is a premium 300 ml polyurethane hybrid sealant designed for professional-grade sealing and bonding. It offers exceptional weather and aging resistance, adheres to a wide range of substrates including wood, metals, ceramics, and plastics, and features a flexible, paintable, and sandable finish. Free from solvents, silicone, and PVC, it ensures a durable, eco-conscious seal with high electrical resistance, making it ideal for demanding construction and repair projects.

Specifications

ASIN	B00A9UK1TQ
Best Sellers Rank	13,438 in Automotive ( See Top 100 in Automotive ) 150 in Fillers, Adhesives & Sealants
Brand	Sika
Colour	Weiß
Country Of Origin	Germany
Customer Reviews	4.6 4.6 out of 5 stars (7,274)
Full Cure Time	3E+1 Minutes
Global Trade Identification Number	07611237142116
Item Form	Paste
Item Type Name	Sika Flex-521UV Weatherproof Hybrid Sealant
Item Weight	0.42 Kilograms
Liquid Volume	300 Millilitres
Manufacturer	Sika
Manufacturer Part Number	54864
Material	Polyurethane Silicone silicone Polyvinyl chloride
Model Number	54864
Number of Items	1
Product Warranty	Product guarantees 0 months.
Surface Recommendation	Wall, ceiling, door, window
Tensile Strength	1500 Pounds Per Square Inch
Unit Count	300.0 millilitre
Water Resistance Level	Water Resistant

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Our prices include the product cost, international shipping, import duties, customs clearance, and local delivery charges. We handle all customs and import procedures, ensuring there are no hidden fees upon delivery. PRO members receive additional benefits including free shipping.

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₱3404

Duties & taxes included

In stock

Sold byAmazon PhilippinesDelivered byDesertcartCustomer service byDesertcartReturns14 days · 30 with PRO

Buyer Protection · Full refund if your order doesn't arrive as described.

Desertcart purchases this item on your behalf and handles shipping, customs, and support to Philippines.

Secure transaction

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TrustScore 4.5 | 7,300+ reviews

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Excellent communication throughout the order process. Product is perfect.

2 weeks ago

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