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Twin Wall to Flex Adaptor Ø 125

National Flues presents the Twin Wall to Flex Adaptor Ø 125 – a must-have transitional component designed for seamless integration between traditional TWPro twin wall systems and MI-Flues multi-fuel liners. Ideal for various applications including wood stoves, gas or oil boilers, and solid fuel appl... More...
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At a Glance

  • - Seamless transition from twin wall systems to flexible liners
  • - Constructed from high-grade 304 and 316 stainless steel
  • - Compressed rockwool insulation (200kg/m³) for optimal heat retention
  • - Fully welded design ensuring durability
  • - Maintains a safe 50mm clearance from combustibles
  • - HETAS approved and CE marked for safety and compliance
  • - Designed for both solid fuel and gas/oil appliances
Now only £50.49
Including VAT Buy with confidence. If you find this cheaper within 48 hours of checkout, we'll refund the difference.

 

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

The Twin Wall to Flex Adaptor Ø 125 is essential for connecting your chimney and flue system, ensuring a secure transition from TWPro twin wall systems to MI-Flues multi-fuel liners. Specifically designed for use with solid fuel and gas/oil appliances, including wood stoves, gas coal effect fires, and boilers, this adaptor guarantees high efficiency and safety. Constructed with 0.4mm thick outer and inner skins made of 304 and 316 grade stainless steel respectively, it boasts insulation of compressed rockwool with a density of 200kg/m³.

Fully welded for additional durability, every part maintains a safe 50mm distance to combustible materials. TWPro components are HETAS Approved and CE marked, with designations EN1856-1 T600 N1 W V2 L50040 G50 and EN1856-1 T200 W V2 L50040 O20. Installation is straightforward, requiring a locking band to secure the parts.

Ensure all transitions occur inside an existing class 1 chimney, with no flexible liner visible externally, for optimal performance.

SKU: 2-125-099

Technical Specifications
ModelTwin Wall to Flex Adaptor Ø 125
SKU2-125-099
Inner Material316L Stainless Steel, 0.4mm thick
Outer Material304 Stainless Steel, 0.4mm thick
InsulationCompressed Rockwool (200kg/m³)
Appliance CompatibilityWood stoves, gas coal effect fires, oil/gas boilers, and other solid fuel appliances
ApprovalsHETAS Approved / CE Marked
DesignationsEN1856-1 T600 N1 W V2 L50040 G50, EN1856-1 T200 W V2 L50040 O20
Minimum Clearance To Combustibles50mm
Installation RequirementLocking band for secure coupling, inside an existing class 1 chimney
Ensure your installation is carried out within an existing class 1 chimney. The adaptor requires a locking band to secure the connection between the twin wall system and the flexible flue liner. It is critical that a minimum distance of 50mm is maintained from any combustible material, such as wood or plasterboard. During installation, verify that the flexible liner is completely concealed within the chimney structure – it must not be visible externally. Follow all manufacturer guidelines and local building regulations to ensure both performance and safety. Optional accessories, like additional locking bands or custom fittings, are available to further secure and optimise your installation if required.

The Twin Wall to Flex Adaptor Ø 125 is suitable for solid fuel and gas/oil appliances, including wood stoves, gas coal effect fires, oil and gas boilers, and other solid fuel appliances.

This adaptor is made from 304 grade stainless steel for the outer skin and 316 grade stainless steel for the inner skin, both measuring 0.4mm in thickness. It also includes compressed rockwool insulation with a density of 200kg/m³.

Yes, it is HETAS Approved and CE marked, meeting designations EN1856-1 T600 N1 W V2 L50040 G50 and EN1856-1 T200 W V2 L50040 O20.

Installation is simple with the use of a locking band to secure the parts together. Ensure that there is a 50mm distance from the outside of the flue to any combustible materials and that the transition occurs inside an existing class 1 chimney.

The safe distance to combustibles is 50mm. Ensure no part of the flue is within 50mm of any combustible material like wood or plasterboard.

No, the flexible flue liner should not be visible outside the brick or clay chimney. The transition must be made entirely inside an existing class 1 chimney.

National Flues offers competitive prices, reliable delivery, and excellent service to both retail and trade customers. Our products, including the Twin Wall to Flex Adaptor Ø 125, ensure quality and compliance with industry standards.
Delivery Information +

We work relentlessly to ensure you get your order fast. Estimated delivery for this product is Friday, April 4th. 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. If you find it cheaper within 48 hours, we'll refund the difference.

Read our buyers guide for this Twin Wall to Flex Adaptor Ø 125

National Flues Ltd Verdict

National Flues highly recommends the Twin Wall to Flex Adaptor Ø 125 for its reliable performance and robust construction. Serving both retail and trade customers, we ensure swift nationwide delivery and unbeatable prices.

The Twin Wall to Flex Adaptor Ø 125 is used to create a seamless transition from TWPro twin wall systems to MI-Flues multi-fuel liners, ensuring safe and efficient ventilation for solid fuel and gas/oil appliances.

National Flues is a trusted supplier of quality fireplaces and flues across the UK, offering competitive prices, dependable delivery, and robust options for both retail and trade customers. Our commitment to quality and customer service has made us a leader in the industry.

 

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Secure your installation with this essential adaptor – order today and upgrade your chimney system!

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