AC Infinity 4 Inch Cloudline H4 Fungiculture Inline Fan with Speed Controller, 212 CFMSpecially built with IP65 sealing for fungiculture to manage humidity and CO2 levels in mushroom fruiting chambers. Specially designed for mushroom growing to quietly ventilate grow spaces and help control indoor climate levels. IP65 rated to ensure performance in high humidity spaces while resisting dust, debris, and moisture. Includes a fan speed controller with precise 10 level control for exact airflow and CO2 buildup prevention. EC motor with PWM