20"W X 20"H [Duct Opening] 4-Way Aluminum Curved Blade Adjustable Air Supply HVAC Diffuser [Outer Dimensions: 21.75"W X 21.75"H] Copper Coil-Insulated Line Set 875" width X 7

875" width X 7

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

actual front end outer dimensions are approximately 20 5/8" width X 10 5/8" height

Actual Filter Size – 29 3/4"w x 27 3/4" x 1"

20"W X 20"H [Duct Opening] 4-Way Aluminum Curved Blade Adjustable Air Supply HVAC Diffuser [Outer Dimensions: 21.75"W X 21.75"H] Copper Coil-Insulated Line Set 875" width X 7+ Product Details Size 20"w X 20"h is the size for the duct opening measurement only, actual front end outer dimensions are 21. 75" width X 21. 75" height. Design Individually adjusting curved blades for better air flow control. Screws Included High Quality Aluminum The premium durable aluminum will never rust and it will never wear through leaving the material with an elegant, beautiful, and smooth surface, adds a luxurious touch to any home.