Fits 16x8 Duct Opening Stamped Steel Return Air Grille Vent Cover Grille for Sidewall and Ceiling in White Surface Dimensions: 17.75"W X 9.75"H (16" W x 8" H Duct Opening) 15" long heavy duty steel

15" long heavy duty steel construction with decor matte black powder coating finish

The Listed size 16"x 16" is for inside duct opening measurement

and rafters

"outside" measurement is the surface you can see after the installation

This steel stamp faced register is for sidewall or ceiling applications

Fits 16x8 Duct Opening Stamped Steel Return Air Grille Vent Cover Grille for Sidewall and Ceiling in White Surface Dimensions: 17.75"W X 9.75"H (16" W x 8" H Duct Opening) 15" long heavy duty steelThe Listed size 16"x8" is for inside duct opening measurement, actual outside dimension is 17. 75"x9. 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