Fits 8x18 Duct Opening Stamped Steel Return Air Grille Vent Cover Grille for Sidewall and Ceiling in White Surface Dimensions: 9.75"W X 19.75"H (8" W x 18" H Duct Opening) Multi-shutter damper with easy handle

Multi-shutter damper with easy handle to adjust desired amount of air flow

The Listed size 14"x10" is for inside duct opening measurement

If the duct opening is 14 x 8

buy a 14x20 grille

actual outside dimension is 14" X 14"

Fits 8x18 Duct Opening Stamped Steel Return Air Grille Vent Cover Grille for Sidewall and Ceiling in White Surface Dimensions: 9.75"W X 19.75"H (8" W x 18" H Duct Opening) Multi-shutter damper with easy handleThe Listed size 8"x18" is for inside duct opening measurement, actual outside dimension is 9. 75"x19. 75" Stamped Face Steel Construction with 1 2" fin spacing for high air flow applications. Screws are included for easy installation White Powder coating with matte finish Individually packed with cardboard box for ultra protection