300mm Length Stainless Twin Wall Flue

The Midtherm HTS Twin Wall Flue – 300mm Length is a durable stainless steel insulated flue section designed for precise mid-length extensions in twin-wall systems.

  • 5″ or 6″ diameters
  • Stainless steel chrome finish
  • Push fit connection (Comes with 1 band)
  • Suitable for solid fuel and gas/ oil

Offers strong construction, secure installation, and reliable high-temperature performance.

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Estimated Delivery: 3-5 Working Days

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    FREE delivery on orders over £1,000

    • 14 day no-hassle returns
    • Full manufacturer warranty included
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    • Dedicated aftercare & ongoing support

     

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    midtherm 300 length twin wall stainless
    300mm Length Stainless Twin Wall Flue

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      Delivery, Click & Collect & Returns Information

      Click & Collect:

      We offer a free Click & Collect service on all products. Select “Click & Collect: Berkshire Showroom (RG7 2PQ)” at checkout to reserve your item.

      If the Add to Basket button is not available, please call 0118 970 1717 or email info@bonfire.co.uk
      to place a Click & Collect order.

      To ensure your item is ready for collection, please contact us in advance to confirm availability, opening times, and collection details.

      View our showroom information


      Delivery Information:

      Our current delivery times are approximately 2-3 working days, depending on stock levels at the time of your order. Once your order is placed, we will contact you to confirm your estimated delivery date and notify you of any potential delays.

      • Delivery costs are calculated at checkout based on your postcode location.
      • Free delivery on orders over £1,000 is available within 100 miles of our showroom (RG7 2PQ).
      • Free delivery is a small van/ sprinter 3 metre (receiver unloads) unless stated otherwise.

      We provide delivery within a 200 mile radius of our Reading, Berkshire showroom. To check if we cover your area, click the link below to learn more about our delivery information. For customers beyond this radius, our products are available for collection only online. Please contact our team for a tailored delivery solution, feel free to contact us at 0118 970 1717 or email us at info@bonfire.co.uk for a prompt, bespoke delivery quote.

      Goods are typically delivered on a small or tail-lift van dependant on your requirements, and if access is restricted (e.g., narrow lanes or steep drives), please contact us before placing your order to discuss alternative arrangements. For standard deliveries, a single driver will deliver the goods to the nearest accessible point. We recommend having at least one other person to assist with unloading.

      The driver can only move goods to the closest accessible area, such as a garage, but due to insurance/ health and safety restrictions, cannot bring items into your home. We advise checking the goods while the driver is still there (up to 15 minutes allowed); if any damage is found, please mark it on the delivery note.

      If you are unavailable on the scheduled delivery date, re-delivery charges may apply, and smaller items may require re-scheduling through the courier.

      Learn more about our delivery information


      Return And Exchange Information:

      We offer a 14 day return policy for customers who change their mind or are not satisfied with their purchase. Returns must be requested within 14 days of receiving your order, and the customer is responsible for return shipping costs.

      Our Non Returnable or Refundable Items Include:

      • All flue systems and chimney components
      • All bespoke and made to order items
      • All unique or one off pieces

      Please order carefully based on your application. Please ask our team any questions if you’re unsure on the product.

      Any damaged items must be reported within 48 hours of delivery to ensure a prompt resolution otherwise we cannot guarantee an exchange or replacement. Please ensure the product is returned in its original condition and packaging for a full refund or exchange.

      re-stocking fee of up to 30% may apply to returned or exchanged items as they will have to go back to the manufacturer. Please note that we are unable to accept returns on flue or chimney systems, as well as products with selectable options, made to order and bespoke items

      Learn more about our return and exchange policy

      The Midtherm HTS 300mm Length Stainless Twin Wall Flue is a precision-engineered insulated section designed to extend single-wall flue systems through walls or ceilings with accuracy and robustness. Its effective fitted length of 252mm supports neat alignment and consistent performance across vertical or angled installations, making it suitable for residential and commercial heating systems. Compatible with wood, multifuel, gas, oil, biomass, and pellet appliances, it provides dependable operation in medium to high-temperature environments.

      Constructed from 0.5mm 316 2B stainless steel for the inner liner and 0.5mm 304 BA stainless steel for the outer casing, the component delivers long-lasting strength and corrosion resistance. Laser-welded seams and machine-formed joints ensure secure, airtight connections, while locking bands supplied with male connectors enhance stability throughout the system. Rated for continuous operation at 450°C with a 4-hour fire rating, it is built to handle demanding conditions safely and efficiently.

      As part of the Midtherm HTS Twin Wall System, this 300mm section meets ISO 9001 manufacturing standards, carries CE certification, and is supported by HETAS registration. Designed for long-term reliability, it features a clean polished stainless steel finish that complements modern installations. When installed and maintained correctly, it is protected by a 20-year warranty.

      Features and Benefits

      • 300mm section with 252mm fitted length
      • 316 stainless steel inner and 304 stainless steel outer construction
      • High-temperature rating up to 450°C
      • Laser-welded seams for consistent, airtight joints
      • Locking bands included for secure assembly
      • Suitable for wood, gas, oil, biomass, multifuel, and pellet systems
      • CE-certified, HETAS-registered, and ISO 9001 manufactured
      • 20-year warranty with registered installation

      Additional information

      Brand

      Midtherm

      Colour

      Stainless Steel

      Country Of Origin

      United Kingdom

      Flue Diameter

      127mm (5"), 150mm (6")

      Fuel Type

      Gas, Multi Fuel

      Material

      Stainless Steel

      Warranty

      20 Years (if registered)

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