36" X 6" ADJUSTABLE AIR SUPPLY DIFFUSER - HVAC Vent Duct Cover Sidewall or Ceiling Color_R-4.2 Yellow + Product Details Size -

+ Product Details Size - 24"w X 20"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 20 5/8" width X 28 5/8" height

All of these grills have dampers

Actual Filter Size – 13 3/4"w x 29 3/4" x 1"

4" X 10" Is The Size For The Duct Opening (floor/vent hole) Measurement Only

36" X 6" ADJUSTABLE AIR SUPPLY DIFFUSER - HVAC Vent Duct Cover Sidewall or Ceiling Color_R-4.2 Yellow + Product Details Size -+ Product Details Size 36"w X 6"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 37. 875" width X 8" 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