20" X 18" Steel Return Air Filter Grille for 1" Filter - Removable Frame - [Outer Dimensions: 22 5/8" X 20 5/8"] Color_White Complies with industry standards of Compatible With Duct 7in Applications This sheet metal DDAG-A-1212

Complies with industry standards of USA: ASTM D-882

but you will appreciate the benefits over the period of time

+ Product Details Size – 8" x 14" or 14" x 8" is the size for the duct opening measurement only

actual front end outer dimensions are approximately 22 5/8" width X 42 5/8" height

+ Product Details Size - 18"w X 32"h is the size for the duct opening measurement only

20" X 18" Steel Return Air Filter Grille for 1" Filter Removable Frame [Outer Dimensions: 22 5 8" X 20 5 8"] Color_White Complies with industry standards of Compatible With Duct 7in Applications This sheet metal DDAG A 1212 Complies with industry standards of USA: ASTM D 882 but you will appreciate the benefits over the period of time