20" X 26" Or 26" X 20" Heavy Duty Floor Grille - Fixed Blades Air Grille - Brown [Outer Dimensions: 21.75 X 27.75] Drop Ceilings / Lay-In + Product Details Size &

+ Product Details Size & Compatibility – The size of the wall angle register boot is 8" X 6" X 4" and it is compatible with duct 4"

+ Product Details Size – Stick-on collar is 14" and it is compatible with duct 14"

+ Product Details Size & Compatibilty - The 8" to 6" round metal pipe reducer & increaser 30 gauge is compatible with duct 8" to 6"

+ Product Details Perfect Fit & Easy Sizing - Designed for a 8" x 12" or 12" x 8" duct opening (measured at the opening)

+ Product Details Size – 16"w X 20"h is the size for the duct opening measurement only

20" X 26" Or 26" X 20" Heavy Duty Floor Grille - Fixed Blades Air Grille - Brown [Outer Dimensions: 21.75 X 27.75] Drop Ceilings / Lay-In + Product Details Size &+ Product Details Size 20"w X 26"h or 26" x 20" is the size for the duct opening measurement only, actual front end outer dimensions are approximately 21. 75" width X 27. 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