Product Video Features The Ventirpro 540 fan is an innovative solution designed for maximum airflow, portability and efficiency. The fan is IP55 certified, dust and waterproof and can run stably in any weather. This powerful system is also equipped with a dehumidifier and anti-freeze thermostat to prevent low-temperature failures. Adjustable humidity range 5%-80% RH for basements, warehouses, and crawl spaces from 3600-5600 Cu.Ft. Functions & Applications Airflow: 540 CFM, ventilation type: air out. The Ventilator fan for damp crawl spaces, basement, attic and garage to reduce humidity. It can increase air circulation to stop condensation and wood rot. Also, used for exhausting vent radon gas, treating wood gases and odors, and preventing them from entering living spaces. Key Features Built-in dehumidistat and freeze protection thermostat.Operating humidity: 5%-80%RH, this High-Flow Powered Ventilator Fan will turn ON/OFF automatically with SET Humidity % Level. The Dehumidistat control will not operate if the freeze protection thermostat senses low outdoor temperatures (35 deg F/3 deg C. ). Built-in Isolation Mesh & IP-55 Rated Axial Fan Isolation Mesh on the back prevent reptiles from gaining access to the crawl space; The Aluminum Zinc Shell with an IP-55 rating Axial Fan, highly resistant to liquids and dust, higher weather-proof, makes it ideal for work in a humid environment with long service life, don't worry it rusts. Easy to Install & Operate Vent Fan 540 CFM Air Out; 15 x 10.2 x 2.8 Inches; 115 Vac ~ 50/60 Hz; 0.51 Amps; Noise: