Greenheck’s Model DFDAF-310 non-actuated fire damper is available in widths up to 144 in. and heights up to 100 in. It features a dynamically rated fire damper with robust airfoil blade construction. Models FSD-311 and FSD-312 also offer widths up to 144 in. and heights up to 100 in. These fire-damper models are designed to protect oversized openings in buildings. They are also designed for fire and smoke control in life safety systems and for airflow control in commercial HVAC and industrial systems.