20" X 18" ALUMINUM RETURN FILTER GRILLE FOR 1" FILTER - EASY AIRFLOW - LINEAR BAR GRILLES 18in diameter + Product Details Size -

+ Product Details Size - 36"w X 16"h is the size for the duct opening measurement only

+ Product Details Size - 17"w X 10"h is the size for the duct opening measurement only

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

+ Product Details Size – 10" x 16" or 16" x 10" is the size for the duct opening measurement only

20" X 18" ALUMINUM RETURN FILTER GRILLE FOR 1" FILTER - EASY AIRFLOW - LINEAR BAR GRILLES 18in diameter + Product Details Size -+ Product Details Size 20"w X 18"h is the size for the duct opening measurement only, [Outer Dimensions: 22. 5"w X 20. 5"h] Actual Filter Size 19 3 4"w x 17 3 4" x 1" High Quality High quality rust free, strong aluminum construction with smooth finished edges for easy and safe use; Filter grille features a user friendly plastic latch that requires no screwdriver for opening. Installation Location Sidewall and ceiling. Design Heavier gauge than needed,