36"W X 34"H [Duct Opening] Steel Air Vent Return Grille - HVAC VENT DUCT COVER DIFFUSER - [Outer Dimensions: 37.75"W X 35.75"H] w26h26 + Product Details Size - Compatible With Duct 7in Applications This sheet metal DDAG-A-1212

+ Product Details Size - 12"w X 22"h is the size for the duct opening measurement only

+ Product Details Size – 30"w X 20"h is the size for the duct opening measurement only

the gap will expand and retract to meet perfect air supply needed

If your hole is 14" wide by 20" tall

Design – Cubic core eggcrate design Offers highest airflow efficiency at almost 95%

36"W X 34"H [Duct Opening] Steel Air Vent Return Grille HVAC VENT DUCT COVER DIFFUSER [Outer Dimensions: 37.75"W X 35.75"H] w26h26 + Product Details Size Compatible With Duct 7in Applications This sheet metal DDAG A 1212 + Product Details Size 12"w X 22"h is the size for the duct opening measurement only + Product Details Size – 30"w X 20"h is the size for the duct opening measurement only