28" x 12" Cube Core Eggcrate Return Air Filter Grille for 1" Filter 10" Round Duct Pipe + Product Details Perfect Fit Height_14in WD G128 hp jblade overlay

+ Product Details Perfect Fit & Easy Sizing - Designed for a 6" x 34" or 34" x 6" duct opening (measured at the opening)

please note that the total outer dimensions of the grille measure 8" in diameter

16" Circular Round Aluminum HVAC Supply Grille Air Diffuser - With Butterfly Damper - Vent Duct Cover

+ Product Details Size - 36"w X 12"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 16 5/8" width X 26 5/8" height -

28" x 12" Cube Core Eggcrate Return Air Filter Grille for 1" Filter 10" Round Duct Pipe + Product Details Perfect Fit Height_14in WD G128 hp jblade overlay + Product Details Perfect Fit & Easy Sizing Designed for a 6" x 34" or 34" x 6" duct opening (measured at the opening) please note that the total outer dimensions of the grille measure 8" in diameter