A/B SF

CENTRIFUGAL FANS AND PROPELLER FANS FOR HEATING AND VENTILATING PURPOSES AND FOR EXHAUSTING SMOKE AND FUMES AND PROVIDING FORCED AND INDUCED DRAFT FOR FURNACES, AIR HEATERS OF THE RADIATOR TYPE UTILIZING STEAM OR HOT WATER FOR HEATING AIR FOR VENTILATING AND INDUSTRIAL PURPOSES, UNIT HEATERS UTILIZING STEAM OR HOT WATER AND COMPRISING BLOWERS AND AIR HEATERS OF THE RADIATOR TYPE FOR HEATING AIR AND VENTILATING PURPOSES, HEAT EXCHANGERS UTILIZING HOT AIR OR HOT EXHAUST GASES FOR HEATING GAS AND AIR, AIR-HUMIDIFYING APPARATUS FOR INCREASING THE HUMIDITY OF THE AIR FOR INDUSTRIAL PURPOSES AS IN WEAVING AND SPINNING MILLS, AND AIR FILTERS OF THE CENTRIFUGAL OR FAN TYPE, THE SCREEN OR SIEVE TYPE, AND OF THE BAFFLE TYPE FOR REMOVING IMPURITIES FROM THE AIR