Seal-it® 211 SILICON-HT

Seal-it® 211 SILICON-HT is a heat-resistant, high-quality, acetoxy-curing sealant that is specially designed for heat-resistant gaskets and/or jointing compound, is based on silicone technology and moisture-cures into a durable rubber that retains its elasticity.



  • Specially developed as a durable heat-resistant, low-compression gasket compound for machinery and engine parts.
  • Heat-resistant sealant for devices and equipment, such as pumps, generators, thermostats, hotplates, stoves, oven parts, boilers, water heaters, central heating units and other heating elements.
  • Heat-resistant sealant, specially designed for installation work in the construction and industrial sectors, such as seals on hot water pipes and hot air ducts/pipes, adapters/fittings, smoke and air exhaust ducts, etc.


  • Heat-resistant, continuous exposure up to +300°C, short/intermittent exposure up to +350°C.
  • Durable, retains elasticity, maximum movement capacity of 25%.
  • Fast acetoxy-curing, solvent-freeCE-certified silicone system.
  • Excellent adhesion properties on many non-porous surfaces, such as metals.
  • Easy to work with, smooth application.
  • Good resistance to UV, weather, water, moisture and ageing.

Application conditions

  • Application temperature (ambient and surface) between +5°C and +40°C.
  • On stable, compatible, dry, clean, uncontaminated, grease-free and dust-free surfaces.
  • Ensure proper joint dimensions, for proper absorption of any movements.
  • Use a suitable brush to remove any loose particles from the surface.
  • Degrease the surface properly using Seal-it® 510 CLEANER.
  • Seal-it® 211 SILICON-HT 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.
  • Use Seal-it® 550 FINISH to apply a smooth and tight finish, before skin formation.

Standard product line


12 x 310ml cartridge

12 x 200ml pressure pack







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


  • EN 15651-1: F-EXT-INT 25LM
  • EN 15651-2: G 25LM
  • EN 15651-3: XS1

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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