Fits 20x12 Duct Opening Stamped Steel Return Air Grille Vent Cover Grille for Sidewall and Ceiling in White Surface Dimensions: 21.75"W X 13.75"H (20" W x 12" H Duct Opening) Effortless Airflow Control: Our functional

Effortless Airflow Control: Our functional floor register is equipped with an easy-to-use airflow control dial

This product has listed size 12“w X 8”h is for duct opening measurement only

If your duct opening size is 10” x 6”

The Listed size 10"x 3" is for inside duct opening measurement

actual outsize overall dimensions is 16“ wide by 8” high

Fits 20x12 Duct Opening Stamped Steel Return Air Grille Vent Cover Grille for Sidewall and Ceiling in White Surface Dimensions: 21.75"W X 13.75"H (20" W x 12" H Duct Opening) Effortless Airflow Control: Our functionalThe Listed size 20"x12" is for inside duct opening measurement, actual outside dimension is 21. 75"x13. 75" Stamped Face Steel Construction with 1 2" fin spacing for high air flow applications. Screws are included for easy installation White Powder coating with matte finish Individually packed with cardboard box for ultra protection