The Tinman Plenum-26 is a rectangular-shaped HVAC duct work with a 4-inch filter rack return air duct plenum. Made of galvanized steel, it can be installed for updraft or downdraft purposes. It is compatible with various heating and cooling systems such as ducted evaporative cooler, packaged/rooftop furnace, ductless mini split air conditioner, and more. The product comes in a unit quantity of 20.
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