Concentric vent pipe for a gas furnace which is used for both intake and exhaust (pipe thru wall or roof ). Provides the benefit of one assembly rather than two pipes. Thanks very much to the smart Craigslist reader who informed me details. On the assembly it reads "DO NOT BLOCK INTAKE". Assembly measures aprox 9" wide x 9" deep x 39" height. Pick up from North Aurora. Please call or text show contact info
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