Top Clamp - Ø 300
At a Glance
- High-quality 316L stainless steel construction
- Compatible with MI-FLEX 316 and 904 flexible flue liners
- Withstands temperatures up to 600°C (T600 designation)
- Complies with Building Regulations Document J
- Provides robust support to stabilise chimney linings

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 Top Clamp - Ø 300 is a crucial component for ensuring the stability and effectiveness of your chimney system. Perfectly designed for use with MI-FLEX 316 and 904 flexible flue liners, this top clamp provides essential support by bearing the vertical weight of the flue liner at the top of the stack. All MI-FLEX accessories, including this top clamp, comply with Building Regulations Document J, which mandates that a flexible flue liner must be installed completely enclosed inside a masonry chimney.
The top clamp is suitable for appliances operating at temperatures up to 600°C (T600 designation), making it ideal for use with wood (under 20% moisture), smokeless coal, gas, and oil. For optimal functionality, ensure that the chimney stack is fully weatherproofed and of sound construction, and that all chimney pots are in good condition with appropriate flaunching. Regular maintenance and sweeping are essential for safe operation, particularly with solid fuel appliances.
Adhering to recommended cleaning schedules will help prevent blockages and ensure long-term efficiency.
SKU: 20-300-C
Technical Specifications | |
---|---|
SKU | 20-300-C |
Product Name | Top Clamp - u00d8 300 |
Material | 316L Stainless Steel |
Compatibility | MI-FLEX 316 and 904 flexible flue liners |
Temperature Rating | Up to 600u00b0C (T600) |
Fuel Types | Wood (under 20% moisture), Smokeless coal, Gas, Oil |
Compliance | HETAS / CE, Building Regulations Document J |
Finish | Natural / Stainless Steel |
System | MI-FLEX Accessories MF20 |
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.
National Flues Ltd Verdict
The Top Clamp - Ø 300 is one of our top-rated products for reliable chimney flue installations. It offers seamless support and is designed to work perfectly with MI-FLEX flexible flue liners. We deliver nationwide and cater to both retail and trade customers, making us a dependable partner for all your flue solutions.
The Top Clamp - Ø 300 is used to support the vertical weight of a flexible flue liner at the top of a masonry chimney stack.
National Flues specialises in providing high-quality fireplaces and flue solutions nationwide. With an emphasis on unbeatable prices, reliability, and excellent customer service, we cater to both retail and trade customers, offering secure online payments and dependable deliveries.
