Without a power cord, Genius presents a portable speaker you can take just about anywhere, SP-i170. No matter if you're indoor or outdoor, you can always enjoy your favorite music anywhere for up to eight hours with the built-in battery. SP-i170 uses a bass-enhanced 1.5 inch metal driver to make the sound deeper and broader. Charging is simple; just plug it into the USB port of a PC/Notebook. No adaptor is necessary; use SP-i170 with any notebook, cell phone, iPod/iPhone, MP3/MP4 player and CD player that has a standard 3.5mm audio input. For other applications, SP-i170 has a convenient volume knob that you can adjust the volume as you wish. Features include a quick charge USB cable and a pouch for storage.