12" x 12" - 2-Way Extruded Aluminum Ceiling Diffuser Square - HVAC Vent Cover 8" Diameter Actual Filter Size – 15

Actual Filter Size – 15 3/4"w x 7 3/4" x 1"

actual front end outer dimensions are approximately 20 5/8" width X 28 5/8" height

+ Product Details Size - 20"w X 16"h is the size for the duct opening measurement only

Actual Filter Size – 11 3/4"w x 31 3/4" x 1"

12" x 12" - 2-Way Extruded Aluminum Ceiling Diffuser Square - HVAC Vent Cover 8" Diameter Actual Filter Size – 15+ Product Details Size 12" X 12" is the size for the duct opening measurement only, actual front end outer dimensions are 3". Design Equipped with lever for full airflow control; back blades made of black plastic for reduced air noise and discreet appearance; "Opposing" back blades, ensuring they don't overlap, provide precise damper control and superior air dispersion. High Quality Aluminum The premium durable aluminum will never rust and it will