20" x 26" or 26" x 20" Cube Core Eggcrate Return Air Grille Grilles please note that the total

please note that the total outer dimensions of the grille measure 16" in diameter

+ Product Details Size – 18"w X 26"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 16 5/8" width X 26 5/8" height -

Easy Installation – Just pop the diffuser right into the wall duct hole and the side springs will hold it right into place so that it looks clean

20" x 26" or 26" x 20" Cube Core Eggcrate Return Air Grille Grilles please note that the total+ Product Details Size 20" x 26 or 26" x 20" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 21. 75" X 27. 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