36"W X 10"H [Duct Opening] ALUMINUM RETURN GRILLE - Easy Air Flow - Linear Bar Grilles [Outer Dimensions: 37.875"W X 11.875"H] 10" Round Duct Pipe 4" X 12" Is The

4" X 12" Is The Size For The Duct Opening (floor/vent hole) Measurement Only

Actual Filter Size – 17 3/4"w x 31 3/4" x 1"

+ Product Details Size – 6" x 16" or 16" x 6" is the size for the duct opening measurement only

Ideal for Walls & Ceilings: Designed for seamless installation in standard 16" X 16" duct openings

36"W X 10"H [Duct Opening] ALUMINUM RETURN GRILLE - Easy Air Flow - Linear Bar Grilles [Outer Dimensions: 37.875"W X 11.875"H] 10" Round Duct Pipe 4" X 12" Is The+ Product Details Size 36"w X 10"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 37. 875" width X 11. 875" height. High Quality High quality aluminum with counter sunk screw holes (screws included) and no sharp edges. Design Unrestricted airflow For Your HVAC system noise free components no vibrating louvers etc. Powder Coat Finish Smooth, shiny, scratch resistant, beautiful. Looks like it was