• Efficient Ventilation: Mars Hydro 4'' inline fan uses mixed flow design to provide potent 205CFM airflow, along with a variable speed controller to easily manage the fan speed. • Quiet Workspace And Durable Body: ABS housing plastic frame and blades built sturdy body to create a truly quiet growth environment at extremely low noise(26.8dB-A). • Easy Installation: Removable duct ends with latches for quick disassembly and easy maintenance, and 4.9-foot cord length for various installations as you wish. • Basic Parameters: Exhaust Fan size: 4” | Dimensions: 303mm*202mm*190mm . | Weight: 1.7kg. | Airflow: 205 CFM | Noise: 26.8dB-A.