The DuraVent 6DFA-25 is a flexible liner chimney pipe from the DuraFlex Collection. This flex pipe is designed and made to be used for relining masonry chimney. It is also compatible with various application such as natural gas fireplaces, boilers, and water heaters. This flex pipe comes in an Aluminum finish for added durability and is resistance against corrosion. It also features a 6-inch inner diameter and a 25-foot length. It is also a UL certified for meeting the standard for safety. DuraVent is known to be the leader in providing innovative solutions for the venting industry.