The DuraVent 8DP-SS is a starter section from the DuraPlus collection, designed to be used on a triple-wall, all-fuel chimney system. It has a measurement of 8 inches in diameter and a length of 4 inches. This is used to convert the DuraLiner to DuraPlus. It is a UL-listed product and it also has a limited lifetime warranty. Search only for the best and high-quality products for your vent and chimney system. In cooperation with DuraVent, PlumbersStock.com has everything you need at affordable prices. Go find yours now here at PlumbersStock.com!