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BUILDING AND ROOF VENTILATORS OF METAL, WOOD AND COMBINATION METAL AND WOOD, OF THE STATIONARY AND ROTATING TYPES, METAL CONDUCTORS FOR CONDUCTING AIR TO OR FROM A VENTILATOR, METAL FRESH AIR INTAKES AND REGULATORS THEREFOR, STORM HEAD VENTILATORS COMPRISING ORDINARY STATIONARY, RAIN AND/OR SNOWPROOF VENTILATORS