MFSD is a Combination fire and smoke dampers provide an automatic means of localizing areas of smoke and or fire in ventilation systems that is greatly contribute to the safety of life and property in the early stage of fire. It prevents the spread of fire and or smoke through ventilation ductworks or wall openings. These type of dampers offer an effective fire or smoke barrier maintaining the integrity in a fire situation and it is combined with low leakage characteristic for smoke management. automatically upon detection of heat.