Plastic Equipment Pad for HVAC Systems, 36x38 PAD (2Pcs 18x38) Width_14in + Product Details Size – Compatible With Duct 7in Applications This sheet metal DDAG-A-1212

+ Product Details Size – 6"w X 12"h or 12"w X 6"h is the size for the duct opening measurement only

this fitting is perfectly compatible with 18-inch ducts

meets ASTM E 84

Actual Filter Size – 25 3/4"w x 23 3/4" x 1"

+ Product Details Size – 16"w X 22"h pleated MERV 8 filter for HVAC return filter grille - 3 Pack

Plastic Equipment Pad for HVAC Systems, 36x38 PAD (2Pcs 18x38) Width_14in + Product Details Size – Compatible With Duct 7in Applications This sheet metal DDAG A 1212 + Product Details Size – 6"w X 12"h or 12"w X 6"h is the size for the duct opening measurement only this fitting is perfectly compatible with 18 inch ducts