Z-Flex 6" x 20' Aluminum Liner Kit d28.25 it is not recommended to

it is not recommended to install larger than 36” sets on Propane Gas

25" 2" 25 lbs

Size: 5" (Top W) x 14" (Bottom W) x 7 1/2" (H)

Depth:  10"

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Z-Flex 6" x 20' Aluminum Liner Kit d28.25 it is not recommended toUL listed aluminum chimney liner kit for use with Category I natural draft gas fired heating equipment and gas fireplaces. Note: For Use with Natural Draft Appliances. Not intended for use with Category II, III, or IV gas burning appliances as defined by the National Fuel Gas Code, NFPA 54, or other appliances that result in condensation or corrosive acids on the liner of the chimney, or that create positive pressures in the chimney system.