36"W X 8"H [Duct Opening] Linear Aluminum Clip-On Bar Return Air Grille [Outer Dimensions: 37.25"W x 9.25"H] Oval to Round 90-Degree Boot + Product Details Size -

+ Product Details Size - 18"w X 18"h X 2"d (for duct opening measurement only)

no exceptions

actual front end outer dimensions are approximately 20 5/8" width X 14 5/8" height -

+ Product Details Size – 22" x 22" is the size for the duct opening measurement only

Optional Butterfly Damper Available At Asin: B007CNEL1W

36"W X 8"H [Duct Opening] Linear Aluminum Clip-On Bar Return Air Grille [Outer Dimensions: 37.25"W x 9.25"H] Oval to Round 90-Degree Boot + Product Details Size -+ Product Details Size 36"W X 8"H is (for duct opening measurement only); actual front end outer dimensions are 37. 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