USB/DACBALHeadphone/Line output3.2 inch touch screen (3 0x4 0)28Names of PartsType-C USB data port2.5mm balanced headphone outputPrevious selection buttonPlay/Pause buttonNext selection buttonPower/Lock buttonVolume control wheelTF card slotPower ON / OFF / Screen LockingOperation Instructions1. Power on: press button and hold it for 3 seconds, then device turns on.""2. Power off: press button and hold it for 3 seconds, then device power off.""3. Screen locking: when the device is powered on, press to lock screen and turn off the LCD display; to unlock it, press " " again.""