34" X 24" Steel Return Air Filter Grille for 1" Filter - Removable Frame - [Outer Dimensions: 36 5/8" X 26 5/8"] w6h6 Whether you're restoring an old

Whether you're restoring an old Victorian or craftsman style home

This simple adjustment reduces HVAC strain

Actual Filter Size – 13 3/4"w x 31 3/4" x 1"

Actual Filter Size – 29 3/4"w x 29 3/4" x 1"

ISO Supply Diffusers perform efficiently with air loadings of 6 to 30 air changes per hour (based on 10 ft

34" X 24" Steel Return Air Filter Grille for 1" Filter - Removable Frame - [Outer Dimensions: 36 5/8" X 26 5/8"] w6h6 Whether you're restoring an old+ Product Details Size 34"w X 24"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 36 5 8" width X 26 5 8" height Actual Filter Size 33 3 4"w x 23 3 4" x 1" High Quality High quality solid stamped steel with counter sunk screw holes (screws included) and no sharp edges Installation Location Sidewall and ceiling Design Removable door face for easy filter change & cleaning uses a 1" thick filter.