It is very convenient when you are away from your PC. The AC to USB Power Adapter is a great power solution for your cell phone, PDA, any USB equipment with USB sockets. It charges quickly as you are at your PC. It let you charge your devices with your USB cable no matter where you are. Plug the adapter into any 110V/220V AC outlet and begin charging. In no time, you'll fully charge your cell phone or PDA battery. The lightweight design of the AC Power Adapter makes it ideal for travel, and far easier to carry than that heavy "power brick" that came with your device! 1) Input voltage: AC100-240V 50-60Hz 2) USB output parameter: Charger: DC5.0V or 5.5V 500-1000mA 3) LED display: a)1 LED 1 color indicates power on b)1 LED dual color, red LED will light up to indicate charging is in processing, green LED will light up to indicate charging is completion 4) Constant charging current and charging voltage, short-circuit protection 5) Perfect for charging your cell phone, mp3, PDA and any USB equipment with USB sockets via your USB charging cable.