The tinman SUPPLY AIR DUCT PLENUM is a rectangular-shaped plenum made of 26-gauge galvanized steel. It has 5-6" holes in the cap and is compatible with various HVAC systems such as ducted evaporative coolers, packaged/rooftop furnaces, and heat pump split systems. It can be installed in both updraft and downdraft configurations. The product comes in a unit quantity of 20.
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