Explanation of icon.
USB
Function name:USB
Features of the non-stop power supply function equipped with the USB connector via the USB cable, including a signal for both power failure (AC_FAIL) and battery brownout, is sent to the computer causing the computer to shutdown operations.

After the computer shutdown has occurred, a signal will also be sent from the computer (SHUT_DOWN) to the power supply, causing an automatic shutdown of the power outlet.

Download USB driver from here