Exhaust Fan Venturi Frame, For Blade Dia. 12 in, Height 16 in, Width 16 in, Max. Depth 8 3/4 in, Dia. Opening Required 14 1/2 in, Flange Width 1 in, Venturi Depth 2 1/2 in, Frame Material Steel, Frame Finish Galvanized, Dimension A 16 in, Dimension B 3 1/2 in, Dimension C 12 1/4 in, Dimension D 9 in, Includes Mounting Bolts and Slotted Motor Base to Accept 48 or 56 Frame Motor