National Chimney M-Flex 4" x 15" Stainless Steel Standard Liner Kit h22.63 U/Hour rating maximum 593

U/Hour rating maximum 593

Natural Gas BTU

(G) - Shelf Depth - 8 1/2"

Selkirk 6" to 14" Inner Diameter

Part Number IF-BTSS Dimensions L-1

National Chimney M-Flex 4" x 15" Stainless Steel Standard Liner Kit h22.63 U/Hour rating maximum 593M 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