Brand New Round and oval gas vent pipe and fittings are used for residential, commercial and industrial applications Round vent pipe is a listed type "B" gas vent and it's adjustable fittings eliminate all cutting, fitting and special engineering An improved joint design provides for a rapid and secure connection in seconds, the use of our "lock tab" feature gives installers the option of engaging this tab instead of using sheet metal screws Fully tested and listed per UL 441 Limited lifetime warranty The storm collar is attached to the pipe just above the roof flashing Secured with silicone, the storm collar keeps rain from entering through the roof flashing Slide the storm collar over the pipe and secure it with silicone sealant Industry best warranty contact Selkirk for details