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) The Listed size 14"x10" is

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

SMART DESIGN: Adjustable length of 10"-14" to fit in multiple vent sizes

Built in magnets on each side for easy installation

This product has listed size 8“w X 4”h is for duct opening measurement only

Independent cardboard packing for extra protection

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) The Listed size 14"x10" isThe 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