Aluminum Cube Core Return Air Filter Grille with Plenum Box - 24" x 24" T-Bar Lay-in Drop Ceiling sidewall + Product Details Size - Compatible With Duct 7in Applications This sheet metal DDAG-A-1212

+ Product Details Size - 26"w X 8"h is the size for the duct opening measurement only

+ Product Details Size - 16"w X 20"h is the size for the duct opening measurement only

as well as in return air situations

+ Product Details Size - 4"w X 20"h is the size for the duct opening measurement only

Ideal for Walls & Ceilings: Designed for seamless installation in standard 20" X 8" duct openings

Aluminum Cube Core Return Air Filter Grille with Plenum Box 24" x 24" T Bar Lay in Drop Ceiling sidewall + Product Details Size Compatible With Duct 7in Applications This sheet metal DDAG A 1212 + Product Details Size 26"w X 8"h is the size for the duct opening measurement only + Product Details Size 16"w X 20"h is the size for the duct opening measurement only