Dual headphone MP3/WMA playback 8 EQ including USER MODE Voice recording FM tuner USB 2.0 full speed LCD display with blue or 7 colors of backlight 1xAAA battery Plug & play for windows Me or above Voice sampling frequency: 8KHz Compress Rate: 32Kbps-320Kbps Files Transfer Rate: Read: 3.2Mbps; Write: 2. 6Mbps S/N Ration: 90dB Headphone Output Frequency: 5MW+5MW Output Frequency: 20Hz-20KHz Available memory: 128MB/256MB/512MB/1GB