18" X 4" ADJUSTABLE AIR SUPPLY DIFFUSER - HVAC Vent Duct Cover Sidewall or Ceiling w20h20 + Product Details Size –

+ Product Details Size – 30"w X 24"h is the size for the duct opening measurement only

+ Product Details Size - 18"w X 4"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 26 5/8" width X 10 5/8" height

+ Product Details Perfect Fit & Easy Sizing - Designed for a 12" x 20" or 20" x 12" duct opening (measured at the opening)

display === 'none') { dd

18" X 4" ADJUSTABLE AIR SUPPLY DIFFUSER - HVAC Vent Duct Cover Sidewall or Ceiling w20h20 + Product Details Size –+ Product Details Size 18"w X 4"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 19. 875" width X 6" 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