Ultimate portable audio system for the iPod mini Revolutionary MaxxBass technology creates deep bass without a subwoofer 4 custom designed neodymium micro-drivers create crystal clear sound Built-in Docking station provides same synchronisation data transfer and recharging options as iPod dock Extra long battery life (Up to 24Hours) with four AA batteries or via mains adaptor Highly efficient digital amplifier (Class D) produces maximum power Ultra portable lightweight design folds close at 7inches wide 1 inches deep and 4.4inches high Also features auxiliary input jack power and volume control .