Powered by a PC USB port, no batteries and other external power are needed Plug into your PC USB port, it starts to bring you brightness right now, easy to use Ideal for lighting your laptop in the darkness. An ideal companion for students, travelers, office workers Adopts 28 LED as light source, durable, eco-friendly, low power consumption and energy saving Flexible gooseneck design, you can arbitrarily adjust the lighting angle according to your need