12" x 12" - Corner Direction Extruded Aluminum Ceiling Diffuser Square - HVAC Vent Cover with filter + Product Details Size -

+ Product Details Size - 18"w X 20"h is the size for the duct opening measurement only

+ Product Details Size - 16"w X 10"h is the size for the duct opening measurement only

+ Product Details Size - 36"w X 12"h X 2"d (for duct opening measurement only)

actual front end outer dimensions are approximately 18 5/8" width X 27 5/8" height

12" x 12" - Corner Direction Extruded Aluminum Ceiling Diffuser Square - HVAC Vent Cover with filter + Product Details Size -+ 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