Viessmann Air Vent w/ Shut Off Base 3/8in For Vitodens Wb1B/Wb1Bc/Wb1A/B2Hb/B2Ha/Wb2B/Wb2A/Wb2 Series. Replacement 3/8" Air Vent with Shut Off Base for Vitodens Residential Wall-Mounted Gas-Fired Condensing Boilers Vitodens 100-W and 200-W boilers are designed to operate with natural gas and liquid propane gas (LPG) Vitodens 100-W WB1A is designed for operating with natural gas only Check with manufacturer before ordering replacement parts to ensure a proper fit Give the manufacturer the 16-digit boiler serial number or the 12-digit ASME/NB serial number Package Contents: Viessmann Air Vent With Shut Off Base 3/8in For Vitodens Wb1B/Wb1Bc/Wb1A/B2Hb/B2Ha/Wb2B/Wb2A/Wb2 Series Viessmann 7819971: Air Vent w/ Shut Off Base 3/8in For Vitodens Wb1B/Wb1Bc/Wb1A/B2Hb/B2Ha/Wb2B/Wb2A/Wb2 Series