National Chimney M-Flex 6" x 20" Stainless Steel Standard Liner Kit watt354 Optional tie-down kit is available

Optional tie-down kit is available to secure heaters to patio deck as required

Model 940034B Material Aluminum Diameter 3" x 4" Cap Size W 18" x D 18" x H 9" Clearance UL and ULC listed to 1777 standard

1875" (A) x 3" (B) x 5

Simply add fuel as your fire dies down to sustain your smokeless flame

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National Chimney M-Flex 6" x 20" Stainless Steel Standard Liner Kit watt354 Optional tie-down kit is availableM FLEX standard liner kits are used for wood, oil, coal, and gas appliances. Each of our . 006" (CB) and . 005" (CBF) standard kits comes with installation instructions and a lifetime warranty. This lining kit has been installed in venting applications since 1992 and continues to be the most popular "all fuels" kit we offer. We stock 3" 8" inside diameter (ID) as well as 6" 8" outside diameter (OD) in our . 006" (CB). What's Included 1x Installation