16" X 16" ALUMINUM RETURN FILTER GRILLE FOR 1" FILTER - EASY AIRFLOW - LINEAR BAR GRILLES w25h25 + Product Details Size - 4 X 12 Is CRFG2028 Width_14in

+ Product Details Size - 18"w X 8"h is the size for the duct opening measurement only

5" - SEE BELOW IN DESCRIPTION HOW TO MEASURE A GRILLE

+ Product Details Size – 8" x 20" or 20" x 8" is the size for the duct opening measurement only

actual front end outer dimensions are approximately 28 5/8" width X 18 5/8" height

actual front end outer dimensions are approximately 35

16" X 16" ALUMINUM RETURN FILTER GRILLE FOR 1" FILTER EASY AIRFLOW LINEAR BAR GRILLES w25h25 + Product Details Size 4 X 12 Is CRFG2028 Width_14in + Product Details Size 18"w X 8"h is the size for the duct opening measurement only 5" SEE BELOW IN DESCRIPTION HOW TO MEASURE A GRILLE