The DuraVent 4DFS-FC is a connector from the DuraFlex series, designed to be used in relining your masonry chimney. A drip-free connection, this connector is used to connect DuraFlex SS length to an appliance, flex length, or rigid length. It has an inner diameter of 4 inches and is made of stainless steel. It is also considered as a UL-listed product and is covered by DuraVents limited lifetime warranty. Get the best out of your money by having these high-quality and innovative products from DuraVent. Search yours now here at PlumbersStock.com!