This supply/return air duct plenum measures 21 x 28 x 23.5 inches and is made of galvanized 26 gauge material. It is suitable for use in HVAC and refrigeration systems and is designed for plenum and filter boxes. The brand of the product is Unbranded/Generic and it is a Type Plenum with a Model AIR DUCT. This item is manufactured in the United States.
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