featuring a 6" round duct opening
+ Product Details Size - 26"w X 4"h is the size for the duct opening measurement only
actual front end outer dimensions are approximately 20 5/8" width X 22 5/8" height
+ Product Details Size – 24"w X 30"h is the size for the duct opening measurement only
+ Product Details Size - 8"w X 10"h is the size for the duct opening measurement only
24" X 20" ADJUSTABLE AIR SUPPLY DIFFUSER - HVAC Vent Duct Cover Sidewall or Ceiling Aluminum Bar featuring a 6" round duct+ Product Details Size 24"w X 20"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 25. 875" width X 22" 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