Seal-it® 340 CRYSTAL

Seal-it® 340 CRYSTAL is a crystal-clear, high-quality, professional adhesive sealant for light adhesion and sealing of connecting joints that is based on MS-Polymer® technology and moisture-cures into a durable rubber that retains its elasticity.



  • Crystal-clear sealing, adhesion and installation on practically any surface/material.
  • Seal connecting joints on many building components, especially transparent ones, such as glass, polycarbonate and acrylic.
  • Light adhesion and installation of many building components, especially transparent ones, such as glass, polycarbonate and acrylic.


  • Crystal-clear, blends seamlessly with translucent/transparent components.
  • Durable, retains elasticity, maximum movement capacity of 25%.
  • Versatile and user-friendly: glue, install and seal almost anything, both indoors and out.
  • Excellent adhesion without primer on many surfaces, even moist ones.
  • Paintable with water-based and synthetic paint systems.
  • Usable wet-on-wet, repair with the same material, short tack-free time after skin formation.
  • Free of isocyanate, solvents and silicone.
  • Very low emission: certified EMICODE EC1 PLUS.
  • Good resistance to weather, water, moisture and ageing.
  • Non-corrosive to metals.
  • Odourless, bubble-free and non-shrink fast-curing MS-Polymer® system.


Application conditions

  • Application temperature (ambient and surface) between +5°C and +40°C.
  • On stable, compatible, clean, uncontaminated, grease-free and dust-free surfaces.
  • Use a suitable brush to remove any loose particles from the surface.
  • Degrease the surface properly using Seal-it® 510 CLEANER.
  • Seal-it® 340 CRYSTAL has a broad bonding spectrum, but highly porous surfaces should be pre-treated with Seal-it® 520 PRIMER and non-porous surfaces with minimal bonding should be treated with Seal-it® 525 Clean & Bond.
  • For adhesive applications, apply material vertically (ventilated) in beads spaced between a minimum of 10 cm and a maximum of 20 cm apart. Do not apply in dabs! It is recommended to use double-sided adhesive SEAL-IT® 560 PANELTAPE to support adhesion during the curing process and to achieve the correct adhesive thickness.
  • Use Seal-it® 550 FINISH to apply a smooth and tight finish, before skin formation.

Standard product line


12 x 290ml cartridge



SI-XXX-XXXX-XXX = Article number.
Other colours and/or packaging on request.


  • EN 15651-1: F-INT
  • VOC emission class A+

Technical support department

Connect Products has a state-of-the-art R&D laboratory, where experienced specialists continuously research and develop sealants, adhesives and PU foams. Customers and clients can have products researched, tested and developed by this department. You can also contact us for technical advice, tips, project support, warranty certificates, requests and other technical questions. We will be happy to assist you with high-quality technology.

Call us on +31 (0)183 731 400 or send us an e-mail.

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