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BLACK Fortafix HT Flexseal Silicone - 300ml Cartridge (93-HTFS-B)

Experience the unrivalled performance of BLACK Fortafix HT Flexseal Silicone 300ml Cartridge, a premium high-temperature sealant engineered for the most demanding applications. This heat-resistant, flexible silicone sealant is perfect for both residential and industrial uses, especially in fireplaces, stoves, and flue systems. Read more...
BLACK Fortafix HT Flexseal Silicone - 300ml Cartridge
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Now only £9.99
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At a Glance

  • Withstands temperatures up to 300°C
  • Flexible, high-performance silicone formula
  • 300ml cartridge for extended use
  • Ideal for sealing fireplaces, stoves, and flue joints
  • Trusted Fortafix brand quality

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Phone: 01670 206999
Email: sales@nationalflues.com

The BLACK Fortafix HT Flexseal Silicone in a 300ml cartridge is a premium, flexible, high-temperature sealant designed for rigorous industrial and residential applications. Formulated to withstand temperatures up to an impressive 300°C, this silicone-based sealant is perfect for sealing joints, gaps, and seams in high-heat environments such as fireplaces, stoves, and flue systems. The 300ml cartridge ensures ample material for multiple uses, making it an indispensable product for professionals and DIY enthusiasts alike.

SKU: 93-HTFS-B

Delivery Information* +

We work relentlessly to ensure you get your order fast. Estimated delivery for this product is Friday, November 14th. This is based on current lead times. Bear in mind that it is a busy time of year. If you need a product delivered by a specific time in the next 7 days, then please give us a call on 01670 206 999. Visit our Shipping Information page for more information.

About National Flues Ltd +

We began over 30 years ago as a fireplace shop in the North East. We now supply hundreds of trade professionals and thousands of retail customers, all across the UK, every month. We are still a family owned business, lead by the MD Neil, and always try our best to deliver the best possible experience. We also price match, so give us a call if you find this cheaper and want to buy from us. Visit our about us page to read a bit more.

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Technical Specifications
Cartridge Volume300ml
Temperature ResistanceUp to 300°C
ApplicationFireplaces, Stoves, Flue Systems
PackagingCartridge
BrandFortafix
SKU93-HTFS-B
Price£5.49
Retail Price£9.49
ColourBlack
Sealant TypeHigh-Temperature Flexseal Silicone
For best results, use a standard caulking gun to apply the jacket. Clean and dry the surfaces thoroughly before application to ensure optimal adhesion. Apply a continuous bead of silicone along the joint or seam. Smooth the silicone with a finishing tool or a wet finger for a neat finish. Allow a curing time of 24 to 48 hours depending on ambient conditions. Warning: This product is designed for high-temperature sealing and is not suitable for direct exposure to open flames.

This silicone sealant is ideal for sealing joints, gaps, and seams in high-temperature areas such as fireplaces, stoves, and flue systems.

While the BLACK Fortafix HT Flexseal Silicone can endure temperatures up to 300°C, it is not recommended for direct flame exposure.

The full curing time typically ranges from 24 to 48 hours, depending on the thickness of the application and ambient conditions.

Yes, it is weather-resistant and can be used for both indoor and outdoor high-temperature sealing applications.

Store the unopened cartridge in a cool, dry place. Once opened, ensure the nozzle is sealed tightly to prevent the unused portion from curing.

A standard caulking gun is required to apply the sealant from the 300ml cartridge effectively.

It is recommended to avoid using the BLACK Fortafix HT Flexseal Silicone in food preparation areas due to its chemical composition, though it's generally non-toxic once fully cured.

 

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