Return Air Grille, Overall Depth 3 1/2 in, Overall Height 23 3/4 in, Overall Width 23 3/4 in, Maximum Opening Height 24 in, Maximum Opening Width 24 in, Filter Depth Not Applicable, Filter Height Not Applicable, Filter Width Not Applicable, Grille Color White, Grille Material Steel, Material Steel, Damper Material Not Applicable, Bar Spacing 1/8 in, Face Design Perforated, Airflow Directions One-Way, Adjustable Blades No, Mounting Location Ceiling, Mounting Style Lay-In