6" x 20" or 20" x 6" Cube Core Eggcrate Return Air Grille 12in diameter + Product Details Size –

+ Product Details Size – 16" x 18" or 18" x 16" is the size for the duct opening measurement only

Screws Included - Easy Unrestricted Air Flow For Your HVAC System

1/2" White insulation will give you a good R value of 3

Powder-coat finish

actual front end outer dimensions are approximately 12 5/8" width X 8 5/8" height

6" x 20" or 20" x 6" Cube Core Eggcrate Return Air Grille 12in diameter + Product Details Size –+ Product Details Size 6" x 20" or 20" x 6" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 7. 75" X 21. 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