8" x 10" or 10" x 8" Cube Core Eggcrate Return Air Grille 6in diameter you can attain the diameter

you can attain the diameter of the vent

These Supply Diffusers with integral round necks are recommended for heating

+ Product Details Size – 18" x 20" or 20" x 18" is the size for the duct opening measurement only

actual front end outer dimensions are approximately 28 5/8" width X 18 5/8" height

8" x 10" or 10" x 8" Cube Core Eggcrate Return Air Grille 6in diameter you can attain the diameter+ Product Details Size 8" x 10" or 10" x 8" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 9. 75" X 11. 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