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Sikaflex 521UV - External sealant adhesive 300ml

by Sika
Original price 50,90 zł - Original price 50,90 zł
Original price
50,90 zł
41,38 zł netto
50,90 zł - 50,90 zł
Current price 50,90 zł
41,38 zł netto
Color: black

Stock Available: 40

ikona dostawy Delivery: starts from 11,99 zł - [More]


Capacity: 300ml

Quantity: 1 pc.

Sikaflex 521 UV is a weather resistant 1-component silane terminated polymer (STP) adhesive/sealant with good adhesion to a wide range of materials such as metals, ABS, PC, GRP and wood, normally requiring no special surface preparation . This versatile product is suitable for internal and external sealing.


  • Carton - 12 pcs.


Sikaflex 521 UV has good adhesion to a wide range of substrates and is suitable for flexible sealing and bonding. Suitable substrates include wood, metals, metal primers and paints (two-component systems), ceramics and plastics.

This versatile product is suitable for internal and external sealing. The manufacturer's advice should be sought and tests of the original substrates should be made before using Sikaflex 521 UV on materials susceptible to stress cracking. Test actual substrates and conditions to ensure adhesion and material compatibility.


  • Good resistance to weather conditions and aging processes
  • Good adhesion to a wide range of materials with no special surface preparation required
  • Free from isocyanates and solvents
  • It can be painted
  • Can be sanded
  • Weak smell


Sikaflex 521 UV is generally resistant to fresh water, sea water, diluted acids and diluted alkalis; temporarily resistant to fuels, mineral oils, vegetable and animal fats and oils; not resistant to organic acids, glycolic alcohol, concentrated mineral acids and concentrated bases and solvents.


Surface preparation

Surfaces must be clean, dry and free of grease, oil and dust. Surface preparation depends on the specifics of the substrate and is crucial for a permanent bond. Suggestions for surface preparation can be found in the current issue of the Surface Preparation Guide. It should be taken into account that these recommendations are based on previous experience and must in any case be verified by tests on the original substrates.


Sikaflex 521 UV can be applied at temperatures between 5°C and 40°C, but changes in reactivity and application properties must be considered. The optimum temperature for the substrate and sealant is between 15 ° C and 25 ° C.

Sikaflex 521 UV can be applied with manual, pneumatic or electric piston guns as well as pump equipment.

Smoothing and finishing

Smoothing should be carried out before the skin time expires. It is recommended to use Sika Tooling Agent N for smoothing. Other smoothing agents must be tested for suitability and compatibility prior to use.


Uncured Sikaflex 521 UV can be removed from tools and equipment with Sika Remover-208 or another suitable solvent. After curing, the material can only be removed mechanically. Hands and exposed skin should be washed immediately with Sika Cleaner-350H cleaning towels or a suitable industrial hand cleaner and water. Do not use solvents on the skin

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Time to withdraw from the contract: 14 days

(detailed rules for returning products can be found in the tab: return of goods)


Time for a warranty claim: 2 years

(warranty excluded for entrepreneurs to the extent permitted by law)