Selkirk 3" to 8" 10-Foot Extension Kit (Flexi-Liner)

Size: 3"x10'

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

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✔ Free Returns
✔ No Restocking Fees
✔ Financing Options Available

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Selkirk 3" to 8" 10-Foot Extension Kit

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
1730010 AFE10-03 3"x10' Extension Kit
1740010 AFE10-04 4"x10' Extension Kit
1750010 AFE10-05 5"x10' Extension Kit
1755010 AFE10-05.5 5.5"x10' Extension Kit
1760010 AFE10-06 6"x10' Extension Kit
1770010 AFE10-07 7"x10' Extension Kit
1780010 AFE10-08 8"x10' Extension Kit

CA Residents: 
See Prop 65 WARNING.


Lifetime Limited Warranty

Refer to the Smart Choice Warranty for full warranty details.