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Screw-FIX Adaptor to SW, 1mm - Ø 125 (25-125-MAE1)

National Flues offers the premium Screw-FIX Adaptor to SW, 1mm - Ø 125, a vital solution for creating a seamless transitional joint between rigid single wall flue systems and MI-FLEX flexible liners. Engineered from robust 316L stainless steel, this adaptor ensures compliance with UK Building Regulations and performs reliably under high temperatures. Read more...
Screw-FIX Adaptor to SW, 1mm - Ø 125
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Now only £32.99
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At a Glance

  • 1mm thick 316L stainless steel for superior durability
  • Designed specifically for a seamless transition between a rigid single wall flue system and MI-FLEX liner
  • Complies with UK Building Regulations Document J and CE / HETAS standards
  • Suitable for a range of fuel types including wood (<20% moisture), oil, gas, and smokeless coal
  • Engineered to handle temperatures up to 600°C for high performance under extreme conditions
  • Low stock availability underscores high reliability and demand

We Won't Be Beaten On Price

At National Flues, we continuously monitor competitor prices. This ensures that we consistently offer you the best deals on all our products. Here’s how we keep your costs low:

  • Daily Price Matching: Our team adjusts prices to ensure we stay competitive.
  • Bulk Purchasing Power: We sell a lot, so we can negotiate better rates with suppliers, passing the savings directly to you.
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Price Match Guarantee: If you find the same product cheaper within 48 hours, we’ll match it and refund the difference.

Free Delivery Over £100: Orders over £100 are free delivery (call us if delivery is required outside the mainland UK).

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Have Questions?
Phone: 01670 206999
Email: sales@nationalflues.com

The Screw-FIX Adaptor to SW, 1mm - Ø 125 from National Flues is engineered to provide a reliable transitional joint connecting a rigid single wall flue system to MI-FLEX flexible liners of the same nominal diameter. Manufactured from high-quality 1mm 316L stainless steel, this adaptor ensures durability and robust performance in flue systems. The Screw-Fix Adaptor is designed specifically for use with MI-FLEX 316 and 904 flexible flue liners, completing your chimney system in compliance with UK Building Regulations Document J.

It is compatible with multi-fuel appliances operating at temperatures up to 600°C, and is suitable for wood (with moisture content <20%), smokeless coal, gas, and oil. Ensuring a gas-tight seal, this adaptor should be installed with fire cement, ceramic rope or tape, or high-temperature sealant. It is imperative that the flexible flue liner is entirely contained within a masonry chimney for safety and compliance.

Regular maintenance and sweeping of the chimney system by a competent person, ideally twice a year for solid fuel systems, is crucial to maintain optimal performance.

SKU: 25-125-MAE1

Delivery Information* +

We work relentlessly to ensure you get your order fast. Estimated delivery for this product is Monday, November 17th. 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
Material316L Stainless Steel
Nominal Wall Thickness1mm
Nominal Diameter125mm (Ø 125)
Compatible LinersMI-FLEX 316 and 904
Fuel CompatibilityWood (<20% moisture), Oil, Gas, Smokeless Coal
Temperature RatingUp to 600°C (T600)
Regulatory ComplianceUK Building Regulations Document J, CE / HETAS
Installation AccessoriesFire cement, ceramic rope/tape, or high-temperature sealant
Ensure the MI-FLEX flexible flue liner is completely contained within a masonry chimney before installation. Use fire cement, ceramic rope or tape, or a high-temperature sealant to achieve a gas-tight seal. Always follow manufacturer guidelines and consult with a competent installer. For safety and long-term performance, regular chimney maintenance is essential – have your system inspected and swept at least once a year, and twice a year for solid fuel systems. Do not attempt installation without the appropriate personal protective equipment and tools.

The Screw-Fix Adaptor is used to connect a rigid single wall flue system to a MI-FLEX flexible flue liner of the same diameter, ensuring a smooth and reliable transition.

Yes, the adaptor is suitable for wood (with moisture content <20%), smokeless coal, gas, and oil appliances.

Absolutely. The adaptor complies with the UK Building Regulations Document J, ensuring safe and legal installation within masonry chimneys.

The adaptor is designed to handle temperatures up to 600°C (T600 designation).

To ensure a gas-tight seal, you should use fire cement, ceramic rope or tape, or a high-temperature sealant when installing the adaptor.

It is recommended to have the chimney system swept and inspected at least once a year by a competent person, and twice a year for solid fuel systems.

No, the MI-FLEX flexible flue liner must be completely enclosed within a masonry chimney for safety and regulatory compliance.

 

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