USB flash drive 8GB & USB recorder & mp3 playerDimensions: 45x17x5mmRecording format: WAVMusic format: mp3, WMA, WAVThe device is in record mode until headphones are plugged in.The device is turned on and the indicator light is on. After flashing for 3s, the indicator light turns off.Now it's recording.With headphones plugged in, power on the device and it will play the recorded file or mp3 song.At this point, the indicator light will keep flashing.V+, when plugging in headphones, short press the "+" key to switch to the next song, and long press the "+" key to adjust the volume.V-, when plugging in headphones, short press "-", it will convert the recording file to mp3,A long press will adjust the volume.