20" X 4" ADJUSTABLE AIR SUPPLY DIFFUSER - HVAC Vent Duct Cover Sidewall or Ceiling Compatible with Duct 10" + Product Details Perfect Fit

+ Product Details Perfect Fit & Easy Sizing - Designed for a 16" x 20" OR 20" X 16" duct opening (measured at the opening)

Actual Filter Size – 35 3/4"w x 33 3/4" x 1"

+ Product Details Size - 6"w X 28"h is the size for the duct opening measurement only

Actual Front End Outer Dimensions Are 18" Width X 5" Height - SEE IN DESCRIPTION HOW TO MEASURE A GRILLE

20" X 4" ADJUSTABLE AIR SUPPLY DIFFUSER - HVAC Vent Duct Cover Sidewall or Ceiling Compatible with Duct 10" + Product Details Perfect Fit+ Product Details Size 20"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