18" x 28" or 28" x 18" Cube Core Eggcrate Return Air Grille return filter Box or Other Attachments Needed

Box or Other Attachments Needed

actual front end outer dimensions are approximately 32 5/8" width X 32 5/8" height -

Actual Filter Size – 7 3/4"w x 17 3/4" x 1"

+ Product Details Size – 18" x 26" or 26" x 18" is the size for the duct opening measurement only

Actual Filter Size – 31 3/4"w x 33 3/4" x 1"

18" x 28" or 28" x 18" Cube Core Eggcrate Return Air Grille return filter Box or Other Attachments Needed+ Product Details Size 18" x 28" or 28" x 18" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 19. 75" X 29. 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