USB Car Charger Rocketek 4.2A 2 Port USB Car Charger With Smart Sharing IC for each USB Port, ideal car cigarette lighter charger adapter for all smart phone, tablets and other usb devices. 2 Port 4.2A / 21W smart USB Car Charger ports quickly and easily identify your mobile devices, to provide optimal charging efficiency automatically, it can charges any 2 tablet or smartphone devices at full speed simultaneously. Automatic stops charging when there is danger of overcharging or lower/over voltage with build-in fuse. Safely charge any USB powered devices, iphone/ipad port for Apple Devices (also for Blackberry) and Samsung/HTC port for Non-Apple Mobile phones (like Samsung Galaxy S4, NOTE2 and HTC ONE) or other devices.(Use your existing USB charging cables) Input DC 12V / 24V compatible without interference to Radio, Bluetooth or WiFi Free lifetime technical support and 24-month manufacturer's warranty.