you can attain the diameter of the vent
this 4-way air vent diffuser allows you to precisely control airflow
actual front end outer dimensions are approximately 13
Location – ceiling and sidewall
+ Product Description Introducing our High-Quality Copper Coil
26" X 18" ADJUSTABLE AIR SUPPLY DIFFUSER - HVAC Vent Duct Cover Sidewall or Ceiling w32h32 you can attain the diameter+ Product Details Size 26"w X 18"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 27. 875" width X 20" 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