12" X 12" Baseboard Return Air Grille - HVAC Vent Duct Cover - 7/8" Margin Turnback For Flush Fit With Baseboard Work - White Aluminum - Cube Core + Product Details Size -

+ Product Details Size - 18"w X 36"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 14 5/8" width X 14 5/8" height

with actual front end outer dimensions of 6"

+ Product Details Size – 25"w X 10"h is the size for the duct opening measurement only

12" X 12" Baseboard Return Air Grille - HVAC Vent Duct Cover - 7/8" Margin Turnback For Flush Fit With Baseboard Work - White Aluminum - Cube Core + Product Details Size -+ Product Details Size 12"w X 12"h Is The Size For The Duct Opening Measurement Only, Actual Front End Outer Dimensions Are 13. 75" Width X 13. 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