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) Independent cardboard packing for extra

Independent cardboard packing for extra protection

The Listed size 24"x14" is for inside duct opening measurement

First thing to know about size selection: take the vent cover off the wall or ceiling

6” wide by 5

this is the right size and will fit in well

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) Independent cardboard packing for extraThe 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