Features: Experience the power of efficient air circulation with the inline duct fan, featuring a high speed variable frequency motor and impressive airflows for optimally ventilation. Designed with durability in mind, this inline fan boasts a robusts case and a pure copper outer rotor brushlessness motor that ensures continuous operation without overheating or deformation. For hydroponic enthusiasts, indoor gardeners, and homeowners seeking to enhances their living space's air quality, this duct fan caters to those who prioritize a healthy and comfortable environment. This inline duct fan is a customizable solution for maintaining temperature and humidity levels in your targeted spaces. Can be used with various 12V power adapter, battery power supply, exhaust fans, and can also be used for fire combustion. Specifications: Component:PVC Size:Approx.14cm/5.51inch Inner diameter of circular tube: 5cm/4cm/3.2cm/2.5cm Rotating speed:24300r/minutes Noise:53db The wind pressure: 450pa 25mm air volumes: 30m³/h 32mm air volumes: 35m³/h 40mm air volumes: 45m³/h 50mm air volumes: 55m³/h Input interfaces: 5.5x2.1mm Package Includes: 1pcs Ventilation Exhaust Fan note: 1.Please allow 1-2cm errors due to manual measurement, make sure that you donot mind befores you order. 2.Due to the differences between different monitors, the picture may not reflect the actual colorings of the item. Thanks for your understandings.