18"W X 36"H [Duct Opening] Steel Air Vent Return Grille - HVAC VENT DUCT COVER DIFFUSER - [Outer Dimensions: 19.75"W X 37.75"H] Color_R-4.2 Yellow order a 14x20

order a 14x20

and Diffusers

875" width X 13

The operable dampers

18"W X 36"H [Duct Opening] Steel Air Vent Return Grille - HVAC VENT DUCT COVER DIFFUSER - [Outer Dimensions: 19.75"W X 37.75"H] Color_R-4.2 Yellow order a 14x20+ Product Details Size 18"w X 36"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 19. 75" width X 37. 75" height. Design Easy unrestricted airflow for your HVAC system 50 angled to provide maximum airflow. High Quality Solid stamped steel with counter sunk screw holes (screws included) and no sharp edges. Powder Coat Finish Smooth, shiny, scratch resistant, beautiful. Looks like it was just