The Sony NWZB183B is a personal Walkman which has 4GB of memory capacity meaning it can hold around 900 songs. The battery life of continuous playback is approx. 20 hrs while the charging time is 70mins. It has USB Connection with the added ability of the Drag and Drop feature meaning you can easily transfer music to the device from your computer. It will play MP3 and WMA files and has Bass Boost function.