18"W X 18"H [Duct Opening] ALUMINUM RETURN GRILLE - EASY AIR FLOW - LINEAR BAR GRILLES [OUTER DIMENSIONS: 19.875"W X 19.875"H] Color_Red Oak + Product Details Size -

+ Product Details Size - The listed 10" diameter refers specifically to the size of the duct opening

+ Product Details Size – 36" x 36" is the size for the duct opening measurement only

+ Product Details Perfect Fit & Easy Sizing - Designed for a 16" x 36" OR 36" X 16" duct opening (measured at the opening)

if your hole is 20" wide by 14" tall

18"W X 18"H [Duct Opening] ALUMINUM RETURN GRILLE - EASY AIR FLOW - LINEAR BAR GRILLES [OUTER DIMENSIONS: 19.875"W X 19.875"H] Color_Red Oak + Product Details Size -+ Product Details Size 18"w X 18"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 19. 875" width X 19. 875" height. High Quality High quality aluminum with counter sunk screw holes (screws included) and no sharp edges. Design Unrestricted airflow For Your HVAC system noise free components no vibrating louvers etc. Powder Coat Finish Smooth, shiny, scratch resistant, beautiful. Looks like it was