【40mm Mini Design】Product size is 40 * 40 * 25mm (exclude metal frame). With a design of mini and lightweight, this usb fan can be used in narrow places such as computer hosts, routers, etc. It can also be placed in a small gap on a desk or computer to cool down electronic products. Note: the 40mm fan is small and the speed will increase to achieve the heat dissipation effect, so some noise will be generated during use. | 【2 in 1 USB Fan】Compared to a single fan, the latest upgraded 2 in 1 dual usb fans can cool electronic products from different angles at the same time, which is more efficient. With a large air volume design and an external hard disk box, it can also cool electronic devices such as smart phones, game consoles and personal computers in a few seconds. | 【USB Power Supply, Plug and Play】USB power cable is plug and play. With a speed adjustment switch, there are 3 wind speeds for you to choose, the speeds are respectively L:4000 / M:4800 / H:5500rpm +/- 10% (×2), noise: L:23 / M:25.2 / H:27.3dB. The noise and air volume can be adjusted according to the use environment. Two fans can be connected to one USB cable and run at the same time to improve efficiency. | 【Double Ball Bearing Design & Long Service Life】Adopt high-quality double ball bearing motor, the service life is twice that of ordinary fans, and it can work continuously for a long time. Equipped with a metal frame and finger safety protection to prevent accidental injury during operation. | 【Wide Application】This usb pc fan is not only suitable for cooling equipment such as personal computers, routers and HDDs, but also suitable for AV equipment and game consoles. Simply connect to a device equipped with a USB terminal than can start cooling easily without cumbersome wiring.