20" X 14" Steel Return Air Filter Grille for 1" Filter - Removable Frame - [Outer Dimensions: 22 5/8" X 16 5/8"] Color_Black 85" width X 21 Ducting Components RG2016 FBA-HP Applications The C box

85" width X 21

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

Efficient Airflow Design: The slots are meticulously angled to diversify airflow in two directions

Every part is hand inspected for quality before it is packaged

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

20" X 14" Steel Return Air Filter Grille for 1" Filter Removable Frame [Outer Dimensions: 22 5 8" X 16 5 8"] Color_Black 85" width X 21 Ducting Components RG2016 FBA HP Applications The C box 85" width X 21 + Product Details Size – 18"w X 8"h is the size for the duct opening measurement only