Importer520 White 2-Port USB Car Charger Vehicle Power Adapter with Extra Socket for Nokia Lumia 521(T-Mobile) Brand New non-OEM Polybag Package Short circuit protection. LED charging indication.Intelligent IC chip inside recognizes a full battery and automatically switch to a saver. Extra cigarette lighter socket.Plug never heats or overcharges the battery. Plugs Into Car's Cigarette Lighter You must have a USB charging cable (sold separately) inorder to charge your device with this charger.