... ,built-in Lin-ion 4.USB cable Features: This usb multimedia speakers can link to MP3, MP4, Notebook, CD, DVD, Mobile phone ... , excellent ultra-low sound4)High-efficiency digital Amplifier, enjoy pure and beautyful music 5)Music styles of Classic/Jazz/Pop/Rock ... -in Lithium rechargeable battery & USB power supply (5V, DC) usb multimedia speakers