The tinman supply air duct plenum is a rectangular-shaped HVAC accessory made of 26 gauge galvanized steel. It is designed for updraft and downdraft installations and is compatible with various HVAC systems such as ducted evaporative coolers, packaged/rooftop furnaces, and heat pump split systems. The plenum measures 20 x 16 x 12 inches and comes in a unit quantity of 20. It is an essential part of the HVAC system that helps distribute conditioned air throughout the building.
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