24" X 8" Baseboard Return Air Grille - HVAC Vent Duct Cover - 7/8" Margin Turnback For Flush Fit With Baseboard Work - White Material_Aluminum Actual Filter Size – 11

Actual Filter Size – 11 3/4"w x 5 3/4" x 1"

If your hole is 14" wide by 20" tall

+ Product Details Perfect Fit & Easy Sizing - Designed for a 12" x 36" or 36" x 12" duct opening (measured at the opening)

+ Product Details Perfect Fit & Easy Sizing - Designed for a 36" x 12" OR 12" x 36" duct opening (measured at the opening)

24" X 8" Baseboard Return Air Grille - HVAC Vent Duct Cover - 7/8" Margin Turnback For Flush Fit With Baseboard Work - White Material_Aluminum Actual Filter Size – 11+ Product Details Size 24"w X 8"h Is The Size For The Duct Opening Measurement Only, Actual Front End Outer Dimensions Are 25. 75" Width X 9. 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