PERFECTPRO USB BOX Mode D'emploi page 15

The USB slot is located on the side of the radio behind the rubber cover.
Remove the rubber cover and press in the USB memory device into the
USB slot.
Make sure rubber cover is closed well after use to prevent moist and dirt
from entering the radio.
Using AC power as power source, turn on the radio, the USB power
indicator will turn into green.
Icons during playback USB memory device
GB
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