The Frigidaire 5304509486 Microwave Vent Damper regulates airflow through the ventilation system for compatible over-the-range microwaves. This replacement component opens and closes during operation to direct cooking fumes, steam, and excess heat through the exhaust path while helping prevent outside air from flowing back into the appliance when the fan is not operating. Installed wi... https://www.hnkparts.com/5304509486-frigidaire-damper