DuraVent FasNSeal Flex 12" x 140' Stainless Steel Custom Flex Length extension-kit The back is heavy vinyl

The back is heavy vinyl that lays flat and is non-staining and fire -retardant

The Grand Canyon Stainless Steel Jumbo Burner System by Grand Canyon provides a high-quality burner component to help complete your ideal gas fireplace

Compatible Fireplace Insert DRI2032

Model 051321 Flue Size 13" x 21" Size Width: 11" - 13

DuraVent FasNSeal Flex 12" x 140' Stainless Steel Custom Flex Length extension-kit The back is heavy vinylMade from super ferritic stainless steel. Corrosion resistant. Manufactured with a sure seal locking seam for superior strength and flexibility. The smooth inner wall provides for no output reduction, allowing for full appliance efficiency, ease of cleaning and regular maintenance. The smooth inner wall optimizes gas flow, minimizes back pressure, and facilitates condensate management. Only flexible chimney liner listed to UL 1738 standard. What's