USB Mini Speaker (M201) is not only a portable stereo speaker, but also a MP3 player. It built-in a USB port and SD/MMC card Slot which can read SDHC memory card and USB memory for playing MP3/WMA audio files directly. It also allows to connect to all iPods, MP3, MP4, MD, CD player, notebook, PC, PDA, PSP, mobile phone and other digital products with 3.5mm stereo audio connector. Built in Lithium Ion battery - convenience to use.