12" X 12" 2-Way Air Supply Grille – Steel HVAC Vent Cover with Damper, Wall/Ceiling Register, White Copper Coil Actual Filter Size – 17

Actual Filter Size – 17 3/4"w x 31 3/4" x 1"

+ Product Details Perfect Fit & Easy Sizing - Designed for a 20" x 24" OR 24" x 20" duct opening (measured at the opening)

+ Product Description Upgrade your HVAC system with our 4" Round Air Vent Supply Grille

+ Product Details Size – 28"w X 8"h is the size for the duct opening measurement only

The total outer size of this grille is the listed size plus 1

12" X 12" 2-Way Air Supply Grille – Steel HVAC Vent Cover with Damper, Wall/Ceiling Register, White Copper Coil Actual Filter Size – 17+ Product Details Outer dimensions: 13. 75"W x 13. 75"H fits a 12" X 12" duct opening Durable stamped steel construction ensures long lasting performance Designed for sidewall and ceiling installation with included screws Multi shutter damper with easy lever for precise airflow control Smooth powder coated white finish for a sleek look and scratch resistance + Product Description Maximize your homes airflow with this premium Air Supply Grille air