The 22” e2251Fwu USB powered portable LEDA light-emitting-diode (LED) is a semiconductor diode that emits light when an electric current is applied in the forward direction of the device, as in the simple LED circuit. The effect is a form of electroluminescence where incoherent and narrow-spectrum light is emitted from the p-n junction. monitor is a must-have laptop or desktop accessory. Receives both power and signal via a single USB cable for plug-and-play connection. The monitor does not require a power cord or VGA cable, and comes with a removable base for maximum flexibility.