6" x 36" or 36" x 6" Cube Core Eggcrate Return Air Grille Compatible with Duct 8" Actual Filter Size – 31

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

Actual Filter Size – 19 3/4"w x 24 3/4" x 1"

+ Product Details Size – 25"w X 22"h is the size for the duct opening measurement only

Actual Filter Size – 11 3/4"w x 33 3/4" x 1"

For 14" Round Duct Opening - Spiral or Flex

6" x 36" or 36" x 6" Cube Core Eggcrate Return Air Grille Compatible with Duct 8" Actual Filter Size – 31+ Product Details Size 6" x 36" or 36" x 6" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 7. 75" X 37. 75". High Quality High quality, rust free aluminum construction with smooth finished edges and counter sunk screw holes (screws included); no sharp edges.. Installation Location sidewall and ceiling. Design Cubic core eggcrate design Offers highest airflow efficiency at almost 95%, reducing