28" x 36" or 36" x 28" Cube Core Eggcrate Return Air Grille Copper Coil-Insulated Line Set + Product Description Introducing our

+ Product Description Introducing our High-Quality Copper Coil

+ Product Details Size - 30"w X 4"h is the size for the duct opening measurement only

+ Product Details Size – 12" x 34" or 34" x 12" is the size for the duct opening measurement only

With our extensive selection of Grilles

Actual Filter Size – 19 3/4"w x 19 3/4" x 1"

28" x 36" or 36" x 28" Cube Core Eggcrate Return Air Grille Copper Coil-Insulated Line Set + Product Description Introducing our+ Product Details Size 28" x 36" or 36" x 28" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 29. 75" X 37. 75". High Quality High quality, rust free aluminum construction with smooth finished edges and counter sunk screw holes (screws included); no sharp edges.. Installation Location sidewall and ceiling. Design Cubic core eggcrate design Offers highest airflow efficiency at almost 95%, reducing