Go-anywhere sound quality, only by Sony. Add powerful sound to the music or video on your iPod or iPhone with the RDP-XF300IP portable speaker dock. A slide-out tray snugly holds your music player, and easily closes for travel or changing rooms. The rechargeable lithium ion battery pack provides up to six hours of continuous operation. You'll also experience superb sound via the powerful 40 watt stereo speaker system. Additionally, you can charge your iPod or iPhone while docked to help avoid a drained battery.