Selkirk 3" to 8" Aluminum Flex Length (Flexi-Liner)

Size: 3"x25'

Estimated Arrival: Between and . (To All Contiguous States)

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Selkirk 3" to 8" Aluminum Flex Length

Flexi-Liner Length with coupler and fastener package.

Aluminum Flexible Liner

Flexi-Liner system is designed for relining existing masonry or listed factory-built chimneys and vents serving Category I for natural gas or propane fired appliances.

3" to 8" Diameters:

  • 3000 series aluminum, 2 ply
  • Maximum flue gas temperature 470°F
  • 3" - 8" diameter kits available in 25' and 35' lengths
  • 3" - 5" diameter kits available in 15' lengths
  • Extension kits available in 10', 25' and 35' lengths
  • Can be installed on neutral and negative draft gas appliances
  • B-Vent adaptor available to transition from all brands of Type-B gas vent
  • Insulation sleeve promotes quick heat up, enhances draft and allows zero clearance between liner and masonry chimney 
  • Smart Choice warranty on all components


  • Listed to UL 1777 (Flexible Aluminum Liner installed with Insulation Sleeve) in the U.S.A

Product Code
Part No Size
1730250 AF3-25L 3"x25' Flex Length
1730350 AF3-35L 3"x35' Flex Length
1730500 AF3-50L 3"x50' Flex Length
1740250 AF4-25L 4"x25' Flex Length
1740350 AF4-35L 4"x35' Flex Length
1740500 AF4-50L 4"x50' Flex Length
1750250 AF5-25L 5"x25' Flex Length
1750350 AF5-35L 5"x35' Flex Length
1760250 AF6-25L 6"x25' Flex Length
1760350 AF6-35L 6"x35' Flex Length
1770250 AF7-25L 7"x25' Flex Length
1770350 AF7-35L 7"x35' Flex Length
1780250 AF8-25L 8"x25' Flex Length
1780350 AF8-35L 8"x35' Flex Length

CA Residents: 
See Prop 65 WARNING.


Lifetime Limited Warranty

Refer to the Smart Choice Warranty for full warranty details.