The OrigAudio Volcano speaker can pack a punch of explosion. It has a bass expansion system that you can untwist to create the sound quality of a subwoofer. Not satisfied with just one? You can get multiple Volcanoes and plug them into eachother for an endless stream of music and surround sound. The lithium ion battery is rechargable and charges in under 2 hours. Play time is around 8-10 hours. The dimensions are 2.6 X 2.6 X 2.55 inches and weighs only 3.13 ounces.