30" X 34" Steel Return Air Filter Grille for 1" Filter - Removable Frame - [Outer Dimensions: 32 5/8" X 36 5/8"] 8" Diameter + Product Details Size – Drop Ceilings / Aluminum The set includes a FG1836 HP-1

+ Product Details Size – 8" x 12" or 12" x 8" is the size for the duct opening measurement only

+ Product Details Size - 18"w X 22"h is the size for the duct opening measurement only

1-1/8" - 2334 PSI

actual front end outer dimensions are approximately 20 5/8" width X 26 5/8" height

+ Product Details Size - 26"w X 10"h is the size for the duct opening measurement only

30" X 34" Steel Return Air Filter Grille for 1" Filter Removable Frame [Outer Dimensions: 32 5 8" X 36 5 8"] 8" Diameter + Product Details Size – Drop Ceilings Aluminum The set includes a FG1836 HP 1 + Product Details Size – 8" x 12" or 12" x 8" is the size for the duct opening measurement only + Product Details Size 18"w X 22"h is the size for the duct opening measurement only