4" X 18" Or 18" X 4" Heavy Duty Floor Grille - Fixed Blades Air Grille - Brown [Outer Dimensions: 5.75 X 19.75] w14h14 + Product Details Size –

+ Product Details Size – 4"w X 20"h is the size for the duct opening measurement only

actual front end outer dimensions are 21" width X 21" height

With precise measurements for seamless integration

+ Product Details Perfect Fit & Easy Sizing - Designed for a 34" x 24" Or 24" x 34" duct opening (measured at the opening)

4" X 18" Or 18" X 4" Heavy Duty Floor Grille - Fixed Blades Air Grille - Brown [Outer Dimensions: 5.75 X 19.75] w14h14 + Product Details Size –+ Product Details Size 4"w X 18"h or 18" x 4" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 5. 75" width X 19. 75" height. High Quality High grade steel construction meant for high foot traffic areas. Installation Location Floor. Design Easy drop in installation. Powder Coat Finish Smooth, shiny, scratch resistant, with no sharp edges. Looks like it was just waxed. Quality Packaging Carefully