National Chimney M-Flex Pre-Insulated Wood-Burning Insert Liner Kit

The National Chimney M-Flex Pre-Insulated Wood-Burning Insert Liner Kit, a premium chimney relining solution designed for wood stoves and fireplace inserts. This high-performance pre-insulated chimney liner kit is engineered to improve draft efficiency, enhance safety, and deliver consistent venting performance for demanding residential heating applications.

Built with a durable 316L stainless steel inner liner and a protective aluminum outer casing, this insulated chimney liner system ensures excellent heat retention and long-lasting corrosion resistance. Ideal for wood-burning insert installations, it supports high-temperature operation while improving overall chimney efficiency. Easy to install and built for reliability, this wood stove chimney liner kit is the perfect upgrade for safer, more efficient, and professional-grade venting performance.

Features

• Pre-Insulated Chimney Liner for Maximum Efficiency – Featuring 1/2" thick pre-insulation, this pre-insulated chimney liner kit reduces condensation, improves draft performance, and enhances overall wood-burning stove efficiency while minimizing creosote buildup.
• UL 1777 Listed All-Fuel Chimney Liner System – Certified for safe operation with wood, coal, oil, gas, and pellet appliances, ensuring reliable performance in all all-fuel chimney venting applications.
• Premium 316L Stainless Steel Inner Liner – Constructed from mill-certified 316L stainless steel, this chimney liner system delivers exceptional corrosion resistance, high-heat durability, and long-term reliability for chimney relining projects.
• Flexible Aluminum Outer Casing – Lightweight and highly flexible, the aluminum outer shell chimney liner allows easier handling and installation, especially in tight or offset chimney spaces.
• Enhanced Draft & Reduced Creosote Formation – Insulated design maintains consistent flue temperatures, improving chimney draft efficiency and reducing dangerous creosote accumulation for safer operation.
• Complete Chimney Liner Installation Kit – Includes a stove adapter, rain cap, and 13” x 13” top plate, providing a full chimney relining kit for quick and professional installation.
• Optimized for Wood-Burning Insert Applications – Specifically engineered for wood stove and fireplace insert installations, delivering improved combustion performance and heating efficiency.
• Available in Standard Length Options – Offered in 25 ft and 35 ft lengths, making it suitable for most residential chimney liner replacement projects.
• High Flexibility for Easy Installation – Designed to navigate offsets and existing masonry chimneys with ease, reducing installation time and complexity.
• Transferable Lifetime Warranty Protection – Backed by a lifetime transferable warranty, ensuring long-term confidence and dependable performance.

Specifications

Add additional 1-inch to compensate for 1/2" thickness of insulation.

Warranty

• Limited Lifetime Warranty

Documents & Files

• Product Brochure
• Installation Guide