20"W X 8"H [Duct Opening] Linear Aluminum Clip-On Bar Return Air Grille [Outer Dimensions: 21.25"W x 9.25"H] Top Ceiling Box the actual front end outer

the actual front end outer dimensions are 7" in diameter

also referred to as T-Bar or Lay-in system

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

75"H – fits a 20" X 6" duct opening

+ Product Details Perfect Fit & Easy Sizing - Designed for a 16" x 26" OR 26" X 16" duct opening (measured at the opening)

20"W X 8"H [Duct Opening] Linear Aluminum Clip-On Bar Return Air Grille [Outer Dimensions: 21.25"W x 9.25"H] Top Ceiling Box the actual front end outer+ Product Details Size 20"W X 8"H is (for duct opening measurement only); actual front end outer dimensions are 21. 25" Width X 9. 25" Height. Design Designed for concealed, flush placement on your wall with a 3 8 inch space between louvers, this linear grille comes with an installation frame and clips for easy hook in assembly, ensuring a refined and seamless look. High Quality Aluminum The premium durable aluminum will never rust and it will never