Screw-FIX Register Plate Increaser - Ø 125-150mm (25-125-RPAI)

At a Glance
- Increases flue diameter from 125mm to 150mm
Precision-engineered for MI-FLEX 316 and 904 liners
Built-in cover plate conceals installation hole
Provides secure, gas-tight connections for enhanced safety
Suitable for multiple fuel types including wood, smokeless coal, gas, and oil appliances
Delivery Information +
We work relentlessly to ensure you get your order fast. Estimated delivery for this product is Tuesday, July 1st. This is based on current delivery times for this product. Delivery for products not in our warehouses can be delayed because of third party carriers. If you need a stove, or other bulky product, to be delivered by a specific time in the next 7 days then please give us a call. We can sometimes 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 and you can read in our blog about they types and terms and conditions for warranties. Mi-Flex flue liner, for example, comes with a lifetime guarantee. Give us a call if you want to know about a specific warranty. 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.
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]
- Info
- Specs
- Install
- FAQs
The Screw-FIX Register Plate Increaser - Ø 125-150mm is a precision-engineered component designed for chimneys utilizing MI-FLEX 316 and 904 flexible flue liners. This versatile accessory adapts to varying flue diameters, ensuring a seamless transition from 125mm to 150mm. Conforming to Building Regulations Document J, it must be installed within a masonry chimney and is suitable for wood with <20% moisture, smokeless coal, gas, and oil appliances up to 600°C (T600). The unit features a long tail single wall connection, optimized for secure fitting and gas-tight seals using fire cement, ceramic rope, tape, or high-temperature sealant. Its built-in round cover plate elegantly conceals the installation hole, providing both functionality and aesthetic value.
SKU: 25-125-RPAI
Technical Specifications | |
---|---|
Flue Diameter Increase | 25mm (from 125mm to 150mm) |
Compatible Liner Materials | MI-FLEX 316 and 904 flexible flue liners |
Temperature Rating | Up to 600u00b0C (T600 designation) |
Installation Requirement | Masonry chimney as per Building Regulations Document J |
Sealant Options | Fire cement, ceramic rope, tape, or high-temperature sealant |
Connection Type | Long tail single wall connection |
Finish | Built-in round cover plate for a neat installation |