GRDE&reg; 34W 6.8A 4 USB Ports Car Charger, Powerful Cigarette Lighter USB Charging Station / Dock, Portable Micro USB Car Charger for iPhone, iPad, Apple Watch, Samsung, Phone, Tablet, GPS, etc. (R28-Black) Input DC 12-24V, apply to both DC 12V cars and DC 24V cars. 4 USB ports, max total output 6.8A (1A*2 + 2.4A*2), charging 4 devices simultaneously. Intelligent charging, distribute current at fast possible speed (up to 2.4A for 2 ports, up to 1A for the other 2 ports). Safety protection, prevent overcharge, overcurrent, overvoltage, overload, short circuit, etc. Compatible with most DC 5V USB-Charged devices, like Apple Watch, iPhone, iPad, Samsung Galaxy, Camera, GPS, etc.