Buildmart 12" Single Slot Insulated Plenum Box for Heating and Cooling BRAND NEW -Actual item shown in photos -One unit pulled from box for detailed photos -You will receive each unit packaged in original factory box Details: Ideal for Texas Buildmart 12" Lineal Slot Diffuser - 1 Slot Galvanized sheet metal Plenum Box with foam insulation Total Box Dimensions: L: 13 3/16" W: 2 7/8" H: 11 7/8" Mouth Dimensions: L: 12" W: 1 5/8" Entry size: 6" flex in oval shape This air-distribution box attaches directly to the supply of the HVAC equipment that heats or cools the air If you do not have this size flex, you can use a reducer to modify the size i27.
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