Features: Adjust the speed of your USB fan with this convenient speed regulator, providing a comfortable and quiet environment for electronic devices. Improve cooling efficiency with this user friendly USB fan speed regulator, suitable for various USB fan and easy installation. Suitable for office worker,home users, this USB fan speed regulator offer a practical solution for customizing fan speed according to individual preferences. The wind speed of fan can be adjusted between5V to 9V according to your comfort; USB speed controller 5W for USB ceiling fan, USB desktop fan, laptops fan, phone heat sink Specifications: Component:Plastic Color:Black Length:Approx.66mm/2.6in Input:5V2A Output:5V9V1A Package Includes: 1pc USB Speed Controller note: Please allow 1-2cm errors due to manual measurement,please make sure that you donot mind befores you order. Due to the differences between different monitors, the picture may not reflect the actual item color.