The Moffitt FMVS Continuous Relief Ventilator, constructed from corrosion-resistant FRP products provide superior performance and service life in severe, corrosive environments which include excess heat, moisture and corrosive gases, liquids and particulates. It is completely weather-proof and designed to offer the least possible resistance to natural air movement due to temperature difference and stack effect and to secure the greatest possible siphon action from wind blowing across the storm band. The high-efficiency design of The Moffitt Continuous Relief Ventilators offers considerable savings over powered ventilation costs and virtually no maintenance expense.