3" DuraFlex SW 25" Tee Kit - 3DFSW-25KT

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DuraFlex SW is a smooth inner-wall, flexible stainless steel chimney liner. The smooth inner wall provides for no output reduction allowing for full appliance efficiency. Smooth wall construction eliminates ridges that restrict flue gas flow and collect deposits. The lack of ridges facilitates cleaning and maintenance. DuraFlex SW is ideal for relining masonry chimney for wood and gas burning appliances. Listed to UL 1777 and ULC S635.


  • Diameter: 3"          
  • Construction material: Single wall .005" 316 Stainless Steel
  • Clearances: 0" to Masonry
  • Listings: Listed to UL 1777 and ULC S635
  • Kit Includes: DuraFlex SS Top Plate, DuraFlex SS Teea with Cap, and Duraflex SW Liner

Additional Information

DuraFlex SW smooth wall flexible relining for masonry chimney. Use with gas, wood pellet, oil, or wood appliances. Applications include: fireplace inserts, furnaces, boilers, and water heaters.

Installation Instructions


Chimney Relining Best Practices

Chimney Relining For Gas Appliances

Click here for Home Safety when relining chimneys for gas appliances.


Weight (lbs) 9.00
Brand DuraFlex AL, DuraVent,
Model 3DFSW-25KT
Diameter 3 Inch
Wall Construction Single Wall
Manufacturer Limited Lifetime Warranty