8" x 8" [Duct Opening] Ceiling Supply Diffuser Vent Cover – 2-Way Airflow with Full Aluminum Frame, Back Blades & Opposing Blade Lever Damper [Outer Size: 11" x 11"] RV Mobile Home + Product Details Size -

+ Product Details Size - 4"w X 24"h is the size for the duct opening measurement only

With a 16-inch size

+ Product Details Size & Compatibility – The size of galvanized sheet metal oval stack head with collar is 12" X 6" - 6" and it is compatible with Duct 6"

order a 14x20

8" x 8" [Duct Opening] Ceiling Supply Diffuser Vent Cover – 2-Way Airflow with Full Aluminum Frame, Back Blades & Opposing Blade Lever Damper [Outer Size: 11" x 11"] RV Mobile Home + Product Details Size -+ Product Details Size Refers to duct opening only. The face frame extends roughly 1. 5" on each side. Do not measure the overall grille for sizing. Design All aluminum frame and back blades. Rustproof and built to last in moisture prone environments. Quiet Airflow Opposing blade damper design reduces vibration and noise for smoother air distribution. Clean Finish White powder coated surface resists chips, scratches, and discoloration over time. Easy