12" X 20" Heavy Duty Floor Grille - Fixed Blades Air Grille - Brown [Outer Dimensions: 21.75 X 13.75] flat stamped steel Actual Filter Size – 31

Actual Filter Size – 31 3/4"w x 11 3/4" x 1"

The lightweight yet rigid construction ensures durability without sacrificing ease of handling

The pleats are W-shaped to provide a larger surface area for trapping dander

+ Product Details Size - 12"w X 4"h Is The Size For The Duct Opening Measurement Only

12" X 20" Heavy Duty Floor Grille - Fixed Blades Air Grille - Brown [Outer Dimensions: 21.75 X 13.75] flat stamped steel Actual Filter Size – 31+ Product Details Size 12" x 20" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 21. 75" width X 13. 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 shrink wrapped