20" x 30" or 30" x 20" Cube Core Eggcrate Return Air Grille Compatible With Duct 8in actual front end outer dimensions

actual front end outer dimensions are approximately 21 5/8" width X 31 5/8" height

All of these grills have dampers

Aluminum Garage Door Air Vent Grille Register - With Damper Control Lever For Winter & Summer Settings - With Insect Net Prevent Guard [17

Actual Filter Size – 21 3/4"w x 35 3/4" x 1"

+ Product Details Size – 10" x 14" or 14" x 10" is the size for the duct opening measurement only

20" x 30" or 30" x 20" Cube Core Eggcrate Return Air Grille Compatible With Duct 8in actual front end outer dimensions+ Product Details Size 20" x 30" or 30" x 20" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 21. 75" X 31. 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