The DuraVent 55DFPRO-15K is a basic kit from the DuraFlex Collection. This kit is commonly used with different applications such as fireplace inserts, furnaces, boilers, and water heaters. It features 5.5-inch inner diameter and 15-foot length. It also comes with the top plate, cap, connector, and a flexible liner pipe. This kit doesn't come with a tee. It comes in stainless steel finish for added strength and flexibility. This basic kit is backed with DuraVent limited lifetime warranty. 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. In cooperation with DuraVent, we at PlumbersStock carry high-quality products like this kit for a very affordable price.