USB Controller Board -USB Fan Speed Controller Highlights Generic Brand USB Fan Speed Controller Description: USB fan speed controller, USB fan adjuster. Set the wind speed regulator to several positions. Button with switch. Strong/weak wind is free to adjust. usb fan stepless It is suitable for offices, dormitories, bedsides, etc. Turn the knob clockwise to increase the wind speed. Rotate counterclockwise to reduce the wind speed, and the button has a switch function. Micro USB and male USB are input terminals for connecting power. A female USB socket is used for connection to the ventilator. Specification: Product Name: USB Stepless Working Voltage: DC 4V-12V Output Voltage: DC 2.5-8.0V Rated Power: 5W (Do not overcharge) Testing Temperature: -40~85 Size: 50x44x18mm/1.96x1. 73x0.70inch Package Include: 1 Piece USB Fan Speed Controller