Features: Improved Air Movement: This variable speed duct fan delivers a powerful air movement , ensuring effective ventilation for grow tents, hydroponics, and indoor gardens. Quiet Operation: strong ABS material and advanced blade technology, the fan operates at a sound level under 31dB, providing a peaceful environment. Variable Speed Settings: Featuring a speed adjuster, this fan allows you to modify the air movement to suit various ventilation needs. Easy Installation and Maintenance: With detachable duct ends equipped with securing clip and a space-efficient design, this fan is simple to install and maintain in tight spaces. Wide Ranges of Applications: Suitable for HVAC systems, industrial spaces, and home use, this fan ensures efficient air exchange for a healthy and pleasant environment. Specifications: Component:ABS Power: 40W (4inch),75W (6inch) Air volumes: 310m³/h (4inch),540m³/h (6inch) Wind speed:2600RPM Noise level: less than 31dB Maximums ambients temperature: 104°F / 40°C Voltage: 220V Frequency: 50Hz Fan Size:4'',6'' Type:US Package Includes: 1Set Inline Duct Fan note: Please allow 1mm errors due to manual measurement. Due to the differences between different monitors, the picture may not reflect the actual color of the item.