For the Ultra Oil direct vent option, the flexible vent kit provided by Weil-McLain is the only vent pipe approved for this application.
A vent termination kit is used for venting your pipe out the wall. The kit normally contains specific parts to give the vent termination a clean look as it exits through your wall to the outside. This particular kit, along with the flexible insulated vent pipe, is needed for the direct vent burner applications for the Ultra Oil boilers.