USB-direct Dictation machine with 512 MB built-in memory. MP3 compatible MP3 playback Advanced dictation features like Digital Pitch Control and Voice Operate Recording 10mm loudspeaker diameter with 35mW output power USB direct key 1xAAA battery operated (supplied). Stamina of upto 19 hours. 512MB built-in flash memory to record upto 251 hours Built in microphone. Sensitivity can be manually selected. No seperate software needed