18" X 12" ADJUSTABLE AIR SUPPLY DIFFUSER - HVAC Vent Duct Cover Sidewall or Ceiling Outdoor Vent Covers + Product Details Size -

+ Product Details Size - 8"w X 16"h is the size for the duct opening measurement only

commercial

actual front end outer dimensions are approximately 10 5/8" width X 18 5/8" height

+ Product Details Size - The listed 4" diameter refers specifically to the size of the duct opening

18" X 12" ADJUSTABLE AIR SUPPLY DIFFUSER - HVAC Vent Duct Cover Sidewall or Ceiling Outdoor Vent Covers + Product Details Size -+ Product Details Size 18"w X 12"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 19. 875" width X 14" height. High Quality High quality steel construction, no scuff powder coat durable finish, smooth, shiny, scratch resistant, no sharp edges, 2 recessed screw holes on each side with screws included, screws same color as vent cover, easy installation. Adjustable airflow control Adjustable airflow