What is Sikaflex-521 UV?

Sikaflex-521 UV in black or white (your choice) is a Polyurethane-based hybrid adhesive and sealing mastic, specially formulated for outdoor applications requiring high UV resistance. Perfect for professionals and vehicle fitting enthusiasts, this product guarantees strong fixings and long-lasting waterproof joints.

An innovative product for maximum sealing

Sikaflex-521 UV is designed to offer excellent adhesion on various materials such as: metal, plastic, wood and glass. Its resistance to UV and weathering makes it an ideal choice for outdoor applications. Moreover, it remains flexible even after curing, allowing it to absorb vibrations and movements without compromising the seal.

Multiple uses

This sealing mastic is ideal for bodywork joints, panel connections, roof repairs and sealing joints around windows and doors.

Technical specifications of Sikaflex 521 UV

• Formulation: Polyurethane-based hybrid adhesive and mastic
• Colour (your choice): Black or white
• Skin formation time: 30 minutes
• Complete curing: 24 hours
• Service temperature: -40°C to +90°C
• UV resistance: Excellent
• Flexibility: High, even after curing
• Adhesion: Metal, plastic, wood, glass and other common materials

Instructions for Use

1. Surface Preparation: Clean and dry the surfaces to be bonded.
2. Application: Apply the mastic directly from the cartridge onto the prepared surface.
3. Smoothing: Smooth the joint with an appropriate tool before skin formation.
4. Drying: Leave to dry for 24 hours for complete curing.

What are the advantages of Sikaflex 521 UV mastic?

• Perfect Sealing: Guarantees long-lasting, weather-resistant sealing.
• Flexibility: Maintains its flexibility to absorb vibrations and movements.
• Easy Application: Direct application and easy smoothing.
• Durability: Resistant to UV and extreme weather conditions.

Transform your fitting projects with Sikaflex-521 UV. Offering flexibility, durability and perfect sealing, it is the ideal ally for all your vehicle sealing work.

For fitting your universal windows and bays, also consider our MS Polymer adhesive-mastic without toxic fumes from the Harber brand!