18"W X 24"H [Duct Opening] ALUMINUM RETURN GRILLE - EASY AIR FLOW - LINEAR BAR GRILLES [OUTER DIMENSIONS: 19.875"W X 25.875"H] Blade Ideal for Walls & Ceilings: Product Details Size 12 LO2222 Height_10in

Ideal for Walls & Ceilings: Designed for seamless installation in standard 10" X 8" duct openings

+ Product Details Perfect Fit & Easy Sizing - Designed for a 20" x 12" OR 12" x 20" duct opening (measured at the opening)

+ Product Details Size - 18"w X 26"h X 2"d (for duct opening measurement only)

actual front end outer dimensions are approximately 38 5/8" width X 22 5/8" height -

Actual Filter Size – 24 3/4"w x 13 3/4" x 1"

18"W X 24"H [Duct Opening] ALUMINUM RETURN GRILLE EASY AIR FLOW LINEAR BAR GRILLES [OUTER DIMENSIONS: 19.875"W X 25.875"H] Blade Ideal for Walls & Ceilings: Product Details Size 12 LO2222 Height_10in Ideal for Walls & Ceilings: Designed for seamless installation in standard 10" X 8" duct openings + Product Details Perfect Fit & Easy Sizing Designed for a 20" x 12" OR 12" x 20" duct opening (measured at the opening)