30" X 6" Baseboard Return Air Grille - HVAC Vent Duct Cover - 7/8" Margin Turnback For Flush Fit With Baseboard Work - White 18" Round Duct Pipe + Product Details Perfect Fit

+ Product Details Perfect Fit & Easy Sizing - Designed for a 26" x 36" OR 36" x 26" duct opening (measured at the opening)

+ Product Details Size - 16"w X 14"h X 2"d (for duct opening measurement only)

you can watch this informative video tutorial: How to Measure Your Vent Hole Before Ordering a Grille

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30" X 6" Baseboard Return Air Grille - HVAC Vent Duct Cover - 7/8" Margin Turnback For Flush Fit With Baseboard Work - White 18" Round Duct Pipe + Product Details Perfect Fit+ Product Details Size 30"w X 6"h Is The Size For The Duct Opening Measurement Only, Actual Front End Outer Dimensions Are 31. 75" Width X 7. 75" Height SEE BELOW IN DESCRIPTION How To Measure A Grille Powder Coat Finish Smooth, shiny, scratch resistant, beautiful. Looks like it was just waxed. High Quality Easy unrestricted airflow for your HVAC system 7 8" margin turnback. Carefully Shrink Wrapped With cardboard backing to prevent damage in shipment