16" Circular Round Aluminum HVAC Supply Grille Air Diffuser - With Butterfly Damper - Vent Duct Cover [Outer Dimensions: 18"] w8h8 + Product Details Size –

+ Product Details Size – 34"w X 20"h is the size for the duct opening measurement only

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Equipped with a lever to adjust airflow to your preference

+ Product Details Size - 12"w X 20"h is the size for the duct opening measurement only

16" Circular Round Aluminum HVAC Supply Grille Air Diffuser - With Butterfly Damper - Vent Duct Cover [Outer Dimensions: 18"] w8h8 + Product Details Size –16" Diameter Is The Size For The Duct Opening Measurement Only, Actual Front End Outer Dimensions Are 16" Diameter Incorporated with Integral Butterfly Damper for full Airflow Control Assembeled Before Powder Coat Paint, to Ensure Perfect Smooth Finish Commercial Grade Aluminum Will Never Rust Designed for Warehouses, Factories, Workshops, Gymnasiums & Restaurants Center Core is Removable for Easy Access and Maintence 16" Circular Round Aluminum HVAC