40"W X 6"H [Duct Opening] Linear Aluminum Clip-On Bar Return Air Grille [Outer Dimensions: 41.25"W x 7.25"H] Compatible With Duct 4in + Product Details Size –

+ Product Details Size – 14" x 24" or 24" x 14" is the size for the duct opening measurement only

Check Out This Asin For Matching T-Bar Drop-Ceiling Grille: B007CNEJZK

+ Product Details Size - 25"w X 4"h is the size for the duct opening measurement only

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40"W X 6"H [Duct Opening] Linear Aluminum Clip-On Bar Return Air Grille [Outer Dimensions: 41.25"W x 7.25"H] Compatible With Duct 4in + Product Details Size –+ Product Details Size 40"W X 6"H is (for duct opening measurement only); actual front end outer dimensions are 41. 25" Width X 7. 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