× National Flues
We Won't Be Beaten On Price.
Free Delivery on Orders Over £100
100% 5 Star Reviews on Trustpilot
Free Flue Design Service Available
Need Help? 01670 206999 (8am-5pm)

Long Tail MI-FLEX Adaptor - Ø 125 (20-125-MAELT)

Discover the robust and reliable Long Tail MI-FLEX Adaptor - Ø 125 from National Flues, designed specifically for seamless integration between rigid single wall flue systems and MI-FLEX flexible liners. This high-performance adaptor is built to deliver outstanding performance in a variety of heating applications, whether you’re using wood, oil, gas, or smokeless coal. With a construction of superior 316L stainless steel and an ability to withstand temperatures of up to 600°C, this product stands as a testament to quality, durability and safety. Experience a secure, gas-tight connection that complies with stringent UK Building Regulations, ensuring peace of mind and efficiency in your chimney Read More...
Hover to Zoom / Click for Gallery
£24.49
Give us a call if you find it cheaper and we'll try to price match.

 

Payment Options

At a Glance

  • Crafted from 0.6mm 316L stainless steel for exceptional durability
  • Designed to connect rigid single wall flue systems with MI-FLEX flexible liners
  • Withstands temperatures up to 600°C for safe operation
  • Compatible with wood (under 20% moisture), oil, gas, and smokeless coal
  • Ensures a gas-tight seal when installed with appropriate high-temperature sealant

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.
  • Operational Efficiency: We have streamlined processes to reduce overhead.

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).

“I saved 20% on my purchase compared to other retailers. Exceptional service!” – Jane D.

Have Questions?
Phone: 01670 206999
Email: [email protected]

The Long Tail MI-FLEX Adaptor - Ø 125 is an invaluable component for any chimney system. Crafted from 0.6mm 316 stainless steel, this adaptor serves as a critical connection between a rigid single wall flue system and MI-FLEX flexible flue liners. Designed to withstand temperatures up to 600°C, it’s suitable for various fuel types, including wood with less than 20% moisture, smokeless coal, gas, and oil.

As per Building Regulations Document J, ensure it is fully enclosed within a masonry chimney for optimal performance and safety. The bottom fixing mechanism guarantees a seamless transition between flue systems, providing a gas-tight seal when properly installed with fire cement, ceramic rope, tape, or high-temperature sealant. Regular maintenance and sweeping by a competent person are crucial for longevity and efficiency, particularly for solid fuel applications.

Trust HETAS registered sweeps for professional chimney care.

SKU: 20-125-MAELT

Technical Specifications
Material316L Stainless Steel
Wall Thickness0.6mm
DiameterØ 125
Maximum Temperature600°C
Fuel CompatibilityWood (<20% moisture), Oil, Gas, Smokeless Coal
ApprovalsHETAS / CE
SystemMI-FLEX Accessories MF20
FinishNatural / Stainless Steel
Ensure the adaptor is fully enclosed within a masonry chimney as specified by Building Regulations Document J. Always secure the bottom fixing into the connecting flue below, and the flexible liner above. For a gas-tight seal, apply fire cement, ceramic rope, high-temperature tape, or sealant as recommended. It is crucial that the installation is performed by a competent person, with regular maintenance and sweeping of the chimney system to avoid build-up and potential hazards. Do not use timber or plasterboard enclosures, and follow manufacturer guidelines closely to maintain the integrity and safety of your installation.

The Long Tail MI-FLEX Adaptor is used to connect a rigid single wall flue system to a MI-FLEX flexible flue liner, creating a secure and efficient transitional joint.

The adaptor is made from 0.6mm 316 stainless steel, known for its durability and resistance to high temperatures.

Yes, it is suitable for use with wood (less than 20% moisture), smokeless coal, gas, and oil.

Yes, the adaptor must be fully enclosed inside a masonry chimney, as timber or plasterboard enclosures are not acceptable according to Building Regulations Document J.

Ensure the bottom fixing is secured into the connecting flue below and the flexible flue liner above. Use fire cement, ceramic rope, tape, or high-temperature sealant to create a gas-tight seal.

Regular sweeping and maintenance of the chimney system by a competent person are essential. For solid fuel applications, it's recommended to clean the chimney twice a year.

For solid fuel applications, you can find HETAS registered chimney sweeps at www.hetas.co.uk.
Delivery Information +

We work relentlessly to ensure you get your order fast. Estimated delivery for this product is Wednesday, April 30th. If you need faster stove or fireplace delivery please give us a call. We can often reduce longer lead times if we pay the carrier £25 for express delivery. Visit our Shipping Information page for more information.

Warranty & Returns +

All our products come with warranties. Mi-Flex offers a lifetime guarantee. Returns for damaged items are covered by insurance; non-damaged returns incur return delivery costs.

Price Match Guarantee +

We will match any price like for like on a retail basis. Give us a call if you find it cheaper and want to buy from us.

Read our review in our Long Tail MI-FLEX Adaptor - Ø 125 buyers guide

Compatible and other products that may be of interest...

Choose the Long Tail MI-FLEX Adaptor now to guarantee safety and performance—your chimney system deserves the best.

Your recently viewed products:

Multiple Payment Options- including Klarna, Clearpay, Mastercard, Visa and Paypal