28"W X 28"H [Duct Opening] Steel Air Vent Return Grille - HVAC VENT DUCT COVER DIFFUSER - [Outer Dimensions: 29.75"W X 29.75"H] Powder-Coated + Product Details Size –

+ Product Details Size – 10"w X 6"h is the size for the duct opening measurement only

The first number in a grille size represents the width

R value rating of insulation - r3

5/8" - 2579 PSI

if your hole is 20" wide by 14" tall

28"W X 28"H [Duct Opening] Steel Air Vent Return Grille - HVAC VENT DUCT COVER DIFFUSER - [Outer Dimensions: 29.75"W X 29.75"H] Powder-Coated + Product Details Size –+ Product Details Size 28"w X 28"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 29. 75" width X 29. 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