The devices provide four 5V DC powered USB ports with a total of 3.0A/3.6A/4.0A charging current. Charge most compatible electrical device directly without an adapter. If the devices combined power requirements exceed the power capacity of the USB ports, the charger will shut down to protect your electrical devices. Compatible with USB 2.0/3.0 devices. The USB ports are used to charge portable electronic devices ONLY (NO data transfer capability). Back and side wire for easy installation. UL/CUL Listed. Fully comply with all latest UL 1310 requirements.